Tag Archives: Disease

Congo declares yellow fever epidemic, 1,000 suspected cases

residents reading reports of yellow fever

KINSHASA (Reuters) – Democratic Republic of Congo on Monday declared a yellow fever epidemic in three provinces, including the capital Kinshasa, after confirming 67 cases of the disease, with another 1,000 suspected cases being monitored.

Health Minister Felix Kabange said only seven of the proven cases were indigenous to the Central African country, while 58 were imported from Angola, where the outbreak began. A further two cases came from remote forested areas not linked to the current outbreak. Five people in total have died, Kabange added.

“I declare today a localized epidemic of yellow fever in the provinces of Kinshasa, Kongo Central and Kwango,” Kabange told a news conference.

Kinshasa is the primary concern for global health officials since it has a densely-packed population of more than 12 million and poor healthcare infrastructure.

Yellow fever is transmitted by the same mosquitoes that spread the Zika and dengue viruses, although it is a much more serious disease. The “yellow” in the name refers to the jaundice that affects some infected patients.

The global stockpile of vaccines has already been depleted twice this year to immunize people in Angola, Uganda and Congo. It stands at 6 million doses, but this may not be enough if there are simultaneous outbreaks in multiple highly-populated areas, experts warn.

Almost 18 million doses have been distributed for emergency vaccination campaigns so far in the three African countries.

The current method for making vaccines, using chicken eggs, takes a year.

World Health Organisation (WHO) advisers have recommended using a fifth of the standard dose of vaccine in the event of a global shortage – enough to immunize temporarily but not to give lifelong immunity.

“An epidemic in such a large city (as Kinshasa) is always difficult to handle,” said WHO’s Congo representative Yokouide Allarangar.

A vaccination campaign has been staged in two of the city’s health zones deemed as high risk because the virus is circulating but is not linked to imported cases, he said.

“We need to quickly try to contain these zones where the virus circulates to prevent the disease from spreading to other zones,” he said, adding that a million of the city’s residents have been vaccinated so far.

Manufacturers of the vaccine include the Institut Pasteur, government factories in Brazil and Russia as well as French drugmaker Sanofi.

Congo’s outbreak, since January, comes at a time when political tensions linked to an upcoming presidential election and an economic crisis stoked by a slump in global commodity prices is already putting a huge strain on the country’s stability.

President Joseph Kabila is facing opposition, which has sometimes turned violent, amid concerns that he will try to cling to power beyond the expiry of his mandate at year-end.

(Writing by Tim Cocks; editing by Matthew Mpoke Bigg and G Crosse)

Health agency reports U.S. babies with Zika-related birth defects

Mosquito under microscope, studying Zika

By Bill Berkrot

(Reuters) – Three babies have been born in the United States with birth defects linked to likely Zika virus infections in the mothers during pregnancy, along with three cases of lost pregnancies linked to Zika, federal health officials said on Thursday.

The six cases reported as of June 9 were included in a new U.S. Zika pregnancy registry created by the Centers for Disease Control and Prevention. The agency said it will begin regular reporting of poor outcomes of pregnancies with laboratory evidence of possible Zika virus infection in the 50 states and the District of Columbia.

Zika has caused alarm throughout the Americas since numerous cases of the birth defect microcephaly linked to the mosquito-borne virus were reported in Brazil, the country hardest hit by the current outbreak. The rare birth defect is marked by unusually small head size and potentially severe developmental problems.

The U.S. cases so far involve women who contracted the virus outside the United States in areas with active Zika outbreaks, or were infected through unprotected sex with an infected partner. There have not yet been any cases reported of local transmission of the virus in the United States. Health experts expect local transmission to occur as mosquito season gets underway with warmer weather, especially in Gulf Coast states, such as Florida and Texas.

The CDC declined to provide details of the three cases it reported on Thursday, but said all had brain abnormalities consistent with congenital Zika virus infection. Two U.S. cases of babies with microcephaly previously were reported in Hawaii and New Jersey.

The poor birth outcomes reported include those known to be caused by Zika, such as microcephaly and other severe fetal defects, including calcium deposits in the brain indicating possible brain damage, excess fluid in the brain cavities and surrounding the brain, absent or poorly formed brain structures and abnormal eye development, the CDC said.

“The pattern that we’re seeing here in the U.S. among travelers is very similar to what we’re seeing in other places like Colombia and Brazil,” Dr. Denise Jamieson, co-leader of the CDC Zika pregnancy task force, said in a telephone interview.

Authorities in Brazil have confirmed more than 1,400 cases of microcephaly in babies whose mothers were exposed to Zika during pregnancy.

Lost pregnancies include miscarriage, stillbirths and terminations with evidence of the birth defects. The CDC did not specify the nature of the three reported lost pregnancies, citing privacy concerns about pregnancy outcomes.

The CDC established its registry to monitor pregnancies for a broad range of poor outcomes linked to Zika. It said it plans to issue updated reports every Thursday intended to ensure that information about pregnancy outcomes linked with the Zika virus is publicly available.

The CDC said the information is essential for planning for clinical, public health and other services needed to support pregnant women and families affected by Zika.

“We’re hoping this underscores the importance of pregnant women not traveling to areas of ongoing Zika virus transmission if possible, and if they do need to travel to ensure that they avoid mosquito bites and the risk of sexual transmission,” Jamieson said.

(Reporting by Bill Berkrot; Editing by Will Dunham)

Scientists use climate, population change to predict disease

A mosquito is seen under a microscope at the Greater Los Angeles County Vector Control District in Santa Fe Springs

By Kate Kelland

LONDON (Reuters) – British scientists say they have developed a model that can predict outbreaks of zoonotic diseases – those such as Ebola and Zika that jump from animals to humans – based on changes in climate.

Describing their model as “a major improvement in our understanding of the spread of diseases from animals to people”, the researchers said it could help governments prepare for and respond to disease outbreaks, and to factor in their risk when making policies that might affect the environment.

“Our model can help decision-makers assess the likely impact (on zoonotic disease) of any interventions or change in national or international government policies, such as the conversion of grasslands to agricultural lands,” said Kate Jones, a professor who co-led the study at University College London’s genetics, evolution and environment department.

The model also has the potential to look at the impact of global change on many diseases at once, she said.

Around 60 to 75 percent of emerging infectious diseases are so-called “zoonotic events”, where animal diseases jump into people. Bats in particular are known to carry many zoonotic viruses.

The Ebola and Zika viruses, now well known, both originated in wild animals, as did many others including Rift Valley fever and Lassa fever that affect thousands already and are predicted to spread with changing environmental factors.

Jones’ team used the locations of 408 known Lassa fever outbreaks in West Africa between 1967 and 2012 and the changes in land use and crop yields, temperature and rainfall, behavior and access to health care.

They also identified the sub-species of the multimammate rat that transmits Lassa virus to humans, to map its location against ecological factors.

The model was then developed using this information along with forecasts of climate change, future population density and land-use change.

“Our approach successfully predicts outbreaks of individual diseases by pairing the changes in the host’s distribution as the environment changes with the mechanics of how that disease spreads from animals to people,” said David Redding, who co-led the study.

“It allows us to calculate how often people are likely to come into contact with disease-carrying animals and their risk of the virus spilling over.”

The team tested their new model using Lassa fever, a disease that is endemic across West Africa and is caused by a virus passing to people from rats. Like Ebola, Lassa causes hemorrhagic fever and can be fatal.

The study, published in the journal Methods in Ecology and Evolution, tested the model with Lassa and found the number of infected people will double to 406,000 by 2070 from some 195,000 due to climate change and a growing human population.

(Reporting by Kate Kelland; editing by Andrew Roche)

Presidents, billionaires battle World’s deadliest creature

Workers look for holes in mosquito netting at the A to Z Textile Mills factory producing insecticide-treated bednets in Arusha, Tanzania

By Katy Migiro

ARUSHA, Tanzania (Thomson Reuters Foundation) – Jakaya Kikwete, the former president of Tanzania, recalled arriving at his cousin’s house to find the family arguing about taking their feverish teenage daughter to hospital.

“They were saying: ‘No, no, no, it’s not malaria’,” he said, describing how the family had sought advice from a traditional medicine man who said a jinni, or spirit, had invaded her body.

“They said: ‘If you take this girl to the hospital, if she gets an injection, then that jinni (spirit)… will… suck all her blood’,” Kikwete said.

Ignoring their protests, he took the girl to hospital but it was too late. She died from malaria.

Kikwete, who also lost his brother to malaria as a child, is committed to eradicating the disease, which killed an estimated 438,000 people globally in 2015 – making the mosquito, which transmits it, the world’s deadliest creature.

He and his wife even appear in television adverts, urging Tanzanians to prepare their bednets before they sleep.

“We are looking at 2040 as the most probable date for a malaria-free Africa,” Kikwete, who stepped down as president in November, told reporters at a recent dinner in Dar es Salaam.

“If we continue with the interventions that we have been doing here relentlessly, we should be able to get there.”

THE “E-WORD”

Global plans to eliminate malaria were abandoned in 1969 as the goal was seen as prohibitively complicated and expensive, despite success in eradicating the disease in the 1950s in parts of Europe, North America and the Caribbean.

The “e-word” has been revived in recent years, with support from the world’s richest couple Bill and Melinda Gates and U.S. President Barack Obama, who called malaria a “moral outrage”.

Bill Gates, who Kikwete describes as a “good friend”, aims to eradicate malaria by 2040 and has called for a doubling of funding by 2025.

His goal of permanently ending transmission of the disease between humans and mosquitoes is more ambitious than the Sustainable Development Goal of ending epidemic levels of malaria by 2030.

Spending on malaria, mostly by the United States, surged to $2.7 billion in 2015 from $130 million in 2000, while death rates in Africa have fallen by 66 per cent, according to the World Health Organization (WHO).

The most important investment was the roll out of one billion free bednets. Some 68 percent of malaria cases prevented since 2000 were stopped by these bednets, according to a study by the University of Oxford.

Money was also poured into improved diagnostic tests, better drugs, indoor spraying with insecticide and educating the public to use these tools – rather than blaming witchcraft or buying medication blindly over the counter every time they got a fever.

EVERYTHING IS FREE

In the Tanzanian town of Arusha, overlooked by the dormant volcano Mount Meru, donor-funded bednets and free tests and medicines have made a significant impact.

In a country with a powerful faith in witchcraft and traditional medicine, health officials have worked hard to persuade people to adopt proven methods of preventing and treating the disease.

“There are very few cases of malaria nowadays,” said Pius Dallos, the officer in charge of Kijenge Dispensary, where women sat on wooden benches, cradling their babies.

“Previously… if you didn’t have money, you could die from malaria. But nowadays, everything is free.”

But donors’ ability to maintain – and increase – funding is by no means certain given sluggish global growth and uncertainties over U.S. funding under a new administration.

“The political will to go that final mile may be hard to sustain because it will remain expensive until the end,” Dyann Wirth, a tropical disease expert at Harvard T.H. Chan School of Public Health, told the Thomson Reuters Foundation.

“It’s a question of priority.”

It is unlikely that Africa, which accounted for nine out of 10 of the 214 million cases of malaria in 2015, according to the WHO, could foot the bill itself.

On the edge of Arusha, Africa’s largest bednet manufacturer, A to Z Textile Mills, has been the main source of 50 million free bednets given to Tanzanians between 2009 to 2016.

Giant, noisy warehouses produce insecticide-treated fibres which are woven into round and square blue bednets. Women in green T-shirts work in fast-moving pairs, folding and cutting panels ready for stitching.

Donor funding drives production of the much-needed nets, as many ordinary Tanzanians cannot afford them.

“Demand is not driven by the need (but) by the funding,” said factory director Kalpesh Shah, sitting in front of framed photographs of visits by celebrity campaigners like Bono and Will Smith on the boardroom wall.

Commercial customers account for less than one percent of sales, he said. The Gates-funded Global Fund To Fight HIV, Tuberculosis and Malaria is their main buyer, followed by the U.S. President’s Malaria Initiative.

“The question of sustainability is on everyone’s mind,” said Daniel Moore, acting mission director for the U.S. Agency for International Development (USAID) in Tanzania.

“Right now, we are carrying the load.”

RISK

The failure of the global eradication programme that began in the 1950s casts a shadow over the latest campaign.

As mosquitoes and parasites developed resistance to insecticides and drugs in the 1960s, malaria rebounded in countries like Sri Lanka where once it had been virtually eliminated.

Resistance is becoming a major problem again. But greater efforts are being made to invest in new products that will keep humans one step ahead of evolution.

New tools are also required to eliminate the parasite from ‘asymptomatic carriers’ – people with a few parasites in their blood who don’t fall sick but can act as reservoir and spread the disease when they get bitten again by mosquitoes.

As the number of malaria cases falls, it will become harder to maintain the momentum among donors, governments and ordinary people in endemic regions.

“Without the long term investment of funds and the political commitment to continue the fight, we risk wasting the entire investment,” said Wirth.

“We are going to go back to the situation where we are losing one million children a year in Africa.”

The International Center for Journalists and Malaria No More provided a travel grant for this report

(Reporting by Katy Migiro; Editing by Ros Russell; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women’s rights, trafficking, property rights and climate change. Visit http://news.trust.org to see more stories.)

Dead Illinois resident had bacteria linked to Wisconsin outbreak

(Reuters) – A northern Illinois resident who died after being diagnosed this year with a blood infection known as Elizabethkingia had the same strain of the bacteria linked to more than a dozen deaths in Wisconsin, health officials said on Tuesday.

Neither the resident’s age nor many other details were released, but Melaney Arnold, spokeswoman for the Illinois Department of Public Health (IDPH), said the individual had suffered from underlying health issues.

IDPH officials have sent alerts to hospitals requesting they report all cases of Elizabethkingia and save any specimens for possible laboratory testing, Arnold added in a statement.

The infection has infected 48 mostly elderly people in Wisconsin, killing 15. Both Michigan and Illinois have each reported one death and one person infected, the statement said.

The patients who died in Wisconsin had serious underlying conditions, health officials have said, and it remains unclear whether the bacteria caused all the fatalities.

Wisconsin, Michigan and Illinois investigators are working with Atlanta-based The Centers for Disease Control and Prevention to determine the possible source of the bacteria.

Elizabethkingia bacteria are rarely reported to cause illness in humans, and can sometimes be found in the respiratory tract. Symptoms can include fever, shortness of breath and chills or cellulitis. Confirmation of the illness requires a laboratory test.

(Reporting by Justin Madden; Editing by Daniel Wallis and James Dalgleish)

Zika mystery deepens with evidence of nerve cell infections

Aedes aegypti mosquitoe

By Julie Steenhuysen

CHICAGO (Reuters) – Top Zika investigators now believe that the birth defect microcephaly and the paralyzing Guillain-Barre syndrome may be just the most obvious maladies caused by the mosquito-borne virus.

Fueling that suspicion are recent discoveries of serious brain and spinal cord infections – including encephalitis, meningitis and myelitis – in people exposed to Zika.

Evidence that Zika’s damage may be more varied and widespread than initially believed adds pressure on affected countries to control mosquitoes and prepare to provide intensive – and, in some cases, lifelong – care to more patients. The newly suspected disorders can cause paralysis and permanent disability – a clinical outlook that adds urgency to vaccine development efforts.

Scientists are of two minds about why these new maladies have come into view. The first is that, as the virus is spreading through such large populations, it is revealing aspects of Zika that went unnoticed in earlier outbreaks in remote and sparsely populated areas. The second is that the newly detected disorders are more evidence that the virus has evolved.

“What we’re seeing are the consequences of this virus turning from the African strain to a pandemic strain,” said Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.

The Zika outbreak was first detected in Brazil last year and is spreading through the Americas. It has been linked to thousands of suspected cases of microcephaly, a typically rare birth defect marked by unusually small head size, signaling a problem with brain development. Evidence linking Zika to microcephaly prompted the World Health Organization to declare a global health emergency in February.

The suspicion that Zika acts directly on nerve cells began with autopsies on aborted and stillborn fetuses showing the virus replicating in brain tissues. In addition to microcephaly, researchers reported finding other abnormalities linked with Zika including fetal deaths, placental insufficiency, fetal growth retardation and injury to the central nervous system.

Doctors also are worried that Zika exposure in utero may have hidden effects, such as behavioral problems or learning disabilities, that are not apparent at birth.

“If you have a virus that is toxic enough to produce microcephaly in someone, you could be sure that it will produce a whole series of conditions that we haven’t even begun to understand,” said Dr. Alberto de la Vega, an obstetrician at San Juan’s University Hospital in Puerto Rico.

First discovered in the Zika forest of Uganda in 1947, the virus circulated quietly in Africa and Asia, causing rare infections and producing mild symptoms. A 2013 outbreak in French Polynesia, the largest at that time, led researchers to make the Guillain-Barre link. Other neurological effects were noted but scientists made little of them at the time.

A rare and poorly understood condition, Guillain-Barre can weaken muscles and cause temporary paralysis, often requiring patients to need respirators to breathe.

An estimated 32,000 people in the French Polynesia Zika outbreak were infected, and 42 patients were confirmed to have Guillain-Barre, a 20-fold increase in incidence over the previous four years, the WHO reported. Another 32 patients had other neurological disorders, including encephalitis, meningoencephalitis, myelitis and facial paralysis.

Guillain-Barre is an autoimmune disorder, in which the body attacks itself in the aftermath of an infection. But the newly discovered brain and spinal cord infections are known to be caused by a different mechanism – a direct attack on nerve cells. That has prompted scientists to consider whether the Zika virus also may infect nerves directly in adults, as they already have suspected in fetuses.

In medical journals published last month, doctors described neurological syndromes in two patients that they attributed to Zika. Doctors in Paris diagnosed meningoencephalitis, an infection of both the brain and spinal cord, in an 81-year-old man who was hospitalized after being exposed to Zika on a cruise.

Another French team reported acute myelitis, a paralyzing infection of the spinal cord, in a 15-year-old girl who had been infected with Zika on the French Caribbean island of Guadeloupe.

In its latest surveillance report, the WHO said the two cases “highlight the need to better understand the range of neurological disorders associated with Zika-virus infection.”

Other mosquito-borne viruses – including dengue, Japanese encephalitis and West Nile – are known to directly infect nerve cells in the brain and spinal cord. But such viruses are seldom associated with Guillain-Barre, and never with microcephaly, said Baylor’s Hotez.

POSSIBLE EVOLUTION

In a recent paper, WHO researcher Mary Kay Kindhauser wrote that Zika “appears to have changed in character,” noting its transition from a mild infection to one causing “large outbreaks linked with neurological disorders.”

Scientists studying Zika in Brazil now are reporting the same neurological disorders seen in French Polynesia. From April through July 2015, doctors in Brazil identified a spike in Guillain-Barre cases.

In Salvador, there were roughly 50 reported cases of Guillain-Barre in July alone, far more than would typically be expected, Dr. Albert Ko, a tropical disease expert from Yale University who is studying Zika in the coastal city of Salvador, recently told a research symposium.

“Throughout Brazil, doctors have seen strange, atypical, neurological manifestations,” Ko said told the symposium.

Zika exposed patients have had other neurological problems as well, including acute disseminated encephalomyelitis, which causes inflammation of the myelin, the protective sheath covering nerve fibers in the brain and spinal cord. Other patients experienced tingling, prickling or burning sensations, which are often markers of peripheral nerve damage.

In addition to Brazil and French Polynesia, at least 11 more countries and territories have reported hundreds of cases of Guillain-Barre syndrome linked to Zika. In Brazil, Guillain-Barre cases jumped 19 percent to 1,708 last year.

El Salvador, a country that has an annual average of 196 cases of Guillain-Barre, reported 118 cases in six weeks in December and January.

Zika’s arrival in Colombia in October 2015 was associated with another increase in Guillain-Barre cases. The country typically reports 242 cases of the syndrome a year, or about five a week. But in the five weeks starting in mid-December, Colombia reported 86 cases of Guillain-Barre, or about 17 a week.

Dr. Carlos Pardo-Villamizar, a neurologist at Johns Hopkins University School of Medicine, is studying Zika complications with colleagues in five Colombian research centers. They have seen cases of encephalitis, myelitis and facial paralysis associated with Zika and want to understand what is triggering these complications.

They also want to study whether prior infection with dengue or chikungunya – two related viruses – are contributing to neurological disorders seen in patients with Zika.

Scientists are turning their attention next to Puerto Rico, where Zika is expected to infect hundreds of thousands of residents by year-end.

More cases hold the potential for “a better sense of the full spectrum of disease that Zika is capable of causing,” said Dr. Amesh Adalja of the Center for Health Security at the University of Pittsburgh Medical Center.

(Reporting by Julie Steenhuysen; additional reporting by Anthony Boadle in Brasilia, Brazil; Editing by Michele Gershberg and Lisa Girion)

Zika Spreading in Puerto Rico

A health worker prepares insecticide before fumigating a neighborhood in San Juan

By Julie Steenhuysen

SAN JUAN (Reuters) – The United States faces its first real challenge with the Zika virus on the island territory of Puerto Rico, a part of the nation that is perhaps least prepared to cope with what is expected to be its worst outbreak.

Zika is spreading rapidly in Puerto Rico and is expected to peak in late summer and early fall. By year’s end, public health officials estimate, hundreds of thousands of people will have been infected.

It is the only part of the country that is experiencing a major local outbreak, but the virus is expected to reach southern U.S. states within weeks with warmer temperatures and rising mosquito populations.

Health officials from across the United States are gathering today at the headquarters of the Centers for Disease Control and Prevention in Atlanta to outline a national strategy for combating Zika. In a measure of the concern surrounding the outbreak in Puerto Rico, CDC director Tom Frieden toured the island, meeting with top health officials and local experts last month to assess the situation first-hand.

Puerto Rico is beset with problems already hampering the response: abundant mosquitoes, high levels of insecticide resistance and economic woes that have left vector control in shambles.

“We don’t have good surveillance” here, Frieden said in an interview at the Puerto Rican health department in San Juan during his tour. “We don’t have good control measures.”

First detected in Brazil last year, the Zika outbreak is spreading through the Americas. The World Health Organization declared a global health emergency last month because of growing evidence that Zika can cause microcephaly, a rare birth defect defined by an unusually small head. In adults, the virus has been linked to the typically rare autoimmune disorder, Guillain-Barre syndrome.

EARLY LESSONS

Fighting Zika in Puerto Rico is complicated by the toll of a decade-long recession. Nearly half of its 3.5 million residents live in poverty, and mosquitoes are an accepted nuisance. Puerto Rico has seen repeated outbreaks of dengue and more recently, chikungunya. Both viruses are carried by Aedes aegypti, the same species of mosquito that carries Zika.

“Here in Puerto Rico, we’re really starting from square one,” said Audrey Lenhart, a CDC vector control expert in an interview at the CDC’s Emergency Operations Center in San Juan.

In its latest report, the Puerto Rican health department said there are now 350 confirmed cases of Zika infection, including 40 pregnant women.

“We have a very serious combination of problems,” said Dr. Alberto de la Vega, an obstetrician specializing in high-risk pregnancies at San Juan’s University Hospital at the Puerto Rico Medical Center.

“If you don’t have access to money to buy repellent, to sleep with an air conditioner on so mosquitoes won’t bite you, to have mosquito nets around you and you live in areas where there’s more stagnant water, obviously you have higher risks,” he said.

To mitigate the risk of microcephaly among newborns, the CDC and the Puerto Rican government are distributing Zika protection kits to pregnant women that include condoms to prevent sexual transmission from an infected partner, insect repellent, bed nets and larvicide tablets for standing water that cannot be drained.

De la Vega says many locals are resigned to the idea that everyone in Puerto Rico will be infected. He said he won’t accept that people are “surrendering like that.”

NO VECTOR CONTROL

Government mosquito abatement resources are scarce, with fewer than a dozen trucks equipped with insecticide sprayers. Of the municipalities that do have trucks, most are used to kill nuisance mosquitoes that bite but do not carry disease, said Manuel Lluberas, a Puerto Rico-born entomologist who works at H.D. Hudson Manufacturing, a maker of spraying equipment.

Lluberas, who advises the WHO and the World Bank on vector control programs, said there are a few municipalities that spray insecticide once every seven to 10 days or once every few weeks. Spraying “needs to be done a lot more frequently” to be effective, he said.

Scientists at CDC’s Dengue Laboratory in San Juan have been testing insecticides on mosquitoes gathered from 17 sites on the island. Frieden said in one of the experiments, mosquitoes placed in bottles coated with a commonly effective insecticide “were happily flying around.”

Eliminating Zika will require spraying insecticide indoors on walls, under beds, behind furniture and inside closets, where Aedes aegypti hide. So far, only two insecticides – deltamethrin and bifenthrin – are approved for indoor residual spraying, and researchers have found high levels of resistance to bifenthrin in Puerto Rico.

Mosquito experts have found similar resistance in parts of Texas and California.

“You find resistance in mosquitoes in one locale, and 20 miles away they are not resistant,” said Joseph Conlon, technical advisor for the American Mosquito Control Association, which represents researchers, public health officials and pesticide makers.

Dr. Janet McAllister, a CDC entomologist, said indoor spraying campaigns will be carried out by local contractors, who will target only areas where the mosquitoes hide instead of coating entire walls, as is typically done to control mosquitoes that carry malaria. “People would not really be coming into direct contact with those surfaces,” McAllister said.

She said the CDC does not plan to use experimental methods, including genetically modified mosquitoes, such as those from Intrexon’s Oxitec now being tested in Brazil, or those infected with Wolbochia bacteria that prevent Zika transmission.

Given the urgency of the outbreak, health officials need to focus on known methods of curbing mosquitoes “rather than doing research on things that may or may not work,” she said.

(Reporting by Julie Steenhuysen; Editing by Michele Gershberg and Lisa Girion)

Zika reported in travelers who returned to California, Arkansas and Virginia

Travelers who recently returned to California, Arkansas and Virginia from foreign countries have tested positive for the Zika virus, health officials in those states announced Tuesday.

The Centers for Disease Control and Prevention (CDC) maintains that there haven’t been any people who have contracted the mosquito-borne virus in the United States, though there have been several cases where travelers got infected overseas and brought the virus back with them.

Zika is collecting the attention of public health officials because scientists are studying a possible link between the virus and a rare condition called microcephaly, in which children are born with smaller-than-usual heads. The birth defect can also be caused by other factors, the CDC says.

Still, the CDC has issued travel notices for 22 countries or territories where Zika is currently being spread, urging pregnant women to consider postponing any planned travel to those areas and asking all would-be travelers to “practice enhanced precautions” to prevent mosquito bites.

The three cases announced Tuesday all involved foreign travel.

In a statement, the Virginia Department of Health said the infection was confirmed in “an adult resident of Virginia who recently traveled to a country where Zika virus transmission is ongoing,” but did not elaborate. The infected individual was the state’s first imported Zika case, but isn’t at risk of transmitting the virus because it isn’t currently mosquito season in Virginia.

The Arkansas Department of Health said one of the state’s residents “recently traveled out of the country and had a mild case of Zika.” Officials confirmed the diagnosis late Monday afternoon.

“Arkansas has the kind of mosquitoes that carry Zika virus, so mosquitoes here in Arkansas can become infected with the virus if they bite someone who has Zika,” Dr. Nate Smith, the Arkansas Department of Health Director and State Health Officer, said in a statement. “For this reason, people traveling to countries with Zika should avoid mosquito bites for 10 days after they return.”

The Los Angeles County Department of Public Health said an adolescent girl who traveled to El Salvador last November was the county’s lone confirmed case of Zika, but she has recovered.

“At this time, local transmission is unlikely,” the department said in a statement. “It would require an Aedes mosquito biting a Zika infected person and then biting others.”

The CDC says only about 20 percent of people who are infected with Zika become ill and develop symptoms like fever, rash and joint pain. Most people fully recover from the illness in a week.

The possible link between Zika and microcephaly is a key component of the travel warnings.

The Brazilian Ministry of Health has investigated more than 4,100 microcephaly cases in the past 13 months, according to data released Wednesday. The ministry used to see fewer than 200 cases of the condition every year, though the numbers have surged since Zika arrived in May.

The Hawaii Department of Health has said a child who was recently born with microcephaly there had been infected with Zika, and his mother likely got the virus when she lived in Brazil.

The CDC says it will also be conducting a study to examine a possible link between Zika and Guillain-Barre Syndrome, a nerve disorder than can lead to muscle weakness and paralysis. Many fully recover from the syndrome, the CDC says, though it can be fatal in rare instances.

The World Health Organization is holding an information session on Zika tomorrow.

The organization says it’s possible the virus could cause epidemics in new areas it reaches because people don’t have immunity to it. There’s also currently no vaccine to prevent it.

CDC issues more travel notices about Zika virus

The Centers for Disease Control and Prevention (CDC) on Friday issued more travel notices about the Zika virus, warning travelers about the potential risks of the mosquito-borne illness.

The notices were issued one week after the CDC advised pregnant women who were planning to travel to 14 countries and territories where outbreaks of the virus were occurring to consider postponing their trips while scientists probe a potential tie between Zika and a rare birth defect.

The notices issued Friday added eight additional countries or territories to the list, bringing the total to 22. The warnings are spread throughout the globe and include places in South America, the Caribbean, Central America, Polynesia and more.

Travelers heading to those areas are asked to “practice enhanced precautions” to prevent mosquito bites, which is how the virus is spread. Pregnant women are advised to rethink their travel plans because of Zika’s potential impact on their unborn children.

Last week, the Hawaii Department of Health announced a child born with microcephaly — a birth defect marked by a smaller-than-usual head — had previously been infected with Zika. The department said his mother likely contracted the virus when she was living in Brazil last May.

The Brazilian Ministry of Health reports that there have been 3,893 cases of microcephaly in the country since the virus arrived in May. The country used to see fewer than 200 cases per year.

Children with microcephaly can develop seizures, vision problems and have developmental delays, the CDC says, but it only occurs in 2 to 12 out of every 10,000 births in the United States.

Scientists are still trying to find a conclusive link between Zika and microcephaly, which can be caused by several other factors. Last week, Dr. Lyle Petersen, the director of CDC’s division of vector-borne diseases, told a news briefing the CDC had “the strongest scientific evidence to date” of a link between Zika and “poor pregnancy outcomes,” though more tests were needed.

Still, the warnings and advice for pregnant women continue. Earlier this week, the CDC issued new guidelines about how healthcare providers in the United States should care for pregnant women who had traveled or were planning to travel to areas where Zika was being transmitted.

Only about 1 in 5 people infected with the virus display any signs of illness, the CDC says, and symptoms are generally mild. They include fever, rash and joint pain, and most people recover within a week. The illness is seldom severe and rarely requires hospitalization.

There haven’t been any reports of people contracting the virus in the United States, the CDC says, though there have been some instances where travelers got bit by infected mosquitos overseas and returned home. The mosquitos that transmit Zika are found in the United States, though Dr. Petersen told the news briefing it’s unclear exactly how or if the virus may spread here.

He told reporters the country has seen improvements in anti-mosquito measures, like using air conditioning and window and door screens, which have helped reduce the spread of other mosquito-borne illnesses, like dengue and malaria, in the past. The CDC encourages all travelers to Zika-prone areas to sleep in screened or air-conditioned rooms, as well as wear long clothing and insect repellant, as there is no vaccine or medicine that can currently prevent an infection.

Countries and territories where the CDC has issued travel notices for Zika include Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Suriname, Venezuela, Barbados, Guadeloupe, Haiti, Martinique, Saint Martin, Samoa, Cape Verde, El Salvador, Guatemala, Honduras, Panama, Mexico and Puerto Rico.

Liberia declared Ebola-free, though threat of flare-ups remain

MONROVIA (Reuters) – Liberia was declared free of the Ebola virus by global health experts on Thursday, a milestone that signaled an end to an epidemic in West Africa that has killed more than 11,300 people.

But the World Health Organisation (WHO) warned there could still be flare-ups of the disease in the region, which has suffered the world’s deadliest outbreak over the past two years, as survivors can carry the virus for many months and could pass it on.

Health specialists cautioned against complacency, saying the world was still underprepared for any future outbreaks of the disease.

Liberia was the last affected country to get the all-clear, with no cases of Ebola for 42 days, twice the length of the virus’s “incubation period” – the time elapsed between transmission of the disease and the appearance of symptoms.

“All known chains of transmission have been stopped in West Africa,” the WHO, a U.N. agency, said on Thursday.

The other affected countries, Guinea and Sierra Leone, were declared Ebola-free late last year. There were cases in seven other countries including Nigeria, the United States and Spain, but almost all the deaths were in the West African nations.

“It is the first time since the start of the … epidemic in West Africa two years ago that the three hardest-hit countries had zero cases for at least 42 days,” said WHO’s Liberia representative Alex Gasasira.

The WHO announcement on Thursday is a major step in the fight against a disease that began in the forests of eastern Guinea in December 2013 before spreading to Liberia and Sierra Leone. It overwhelmed medical infrastructure in the region which was ill-equipped to deal with the outbreak, and at its height in late 2014 sparked global fears among the general public.

However the agency urged caution – Liberia had previously twice been declared virus-free, in May and September of 2015, but each time a fresh cluster of cases unexpectedly emerged.

Its capital Monrovia was badly hit during the worst of the epidemic. Inadequate care meant patients lay strewn on the streets or pavements waiting hours for tests and treatment; medical holding pens became growth centers for the disease.

With those memories still fresh, and society and the economy still reeling from the outbreak, the reaction to Thursday’s announcement was muted. There was no signs of celebration such as the “Ebola free” T-shirts that people wore after previous WHO announcements.

“After the first declaration, people were dancing in the street,” said Vivian Lymas Tegli, child protection officer for UNICEF in Monrovia. “But I don’t think there will be any celebrations today. People are tired of Ebola. They feel it is here to stay.”

‘WORLD UNDERPREPARED’

Experts said progress had been made in the region’s response to Ebola, with new cases having dwindled due to public health campaigns, efforts to trace and isolate potential sufferers and the safe treatment and burial of patients and victims.

But it said the countries would still struggle to deal with any future large outbreak of Ebola, which is passed on through blood and bodily fluids and killed around 40 percent of those who contracted the virus.

Hundreds of healthcare workers in both urban and rural communities were among those killed by the disease, a major blow to medical systems in countries which already had among the lowest numbers of doctors per head of population in the world.

“Today’s WHO announcement is welcome news but we must learn from Ebola’s devastating impact and ensure we are better prepared for infectious disease outbreaks,” said Dr Seth Berkley, head of Gavi, the Vaccine Alliance, an organization that aims to increase access to vaccines in poor countries.

“The world is still worryingly underprepared for potential future health threats and a change of mind-set is required to ensure we invest in research and development today to protect ourselves in years to come.”

Experts also warned other tropical diseases posed future threats, including the previously little known mosquito-borne Zika virus, which has been linked to head-related birth defects and is spreading in South America.

Hilde de Clerck, a doctor with Medecins Sans Frontieres who has assisted with five Ebola outbreaks including in Congo, Uganda and the latest epidemic in West Africa, said vigilance was crucial to prevent the re-emergence of the disease, for which there is no proven drug treatment, although researchers have developed a vaccine.

“I think we should not forget about the risk of other outbreaks,” she said. “I am most concerned about some of the basics: hygiene, equipment and training.”

While WHO and other health specialists say another outbreak of this magnitude is unlikely, and much has been learned in terms of monitoring patients and responding to outbreaks, problems remain, including with simple hygiene, such as not washing hands.

“I do really believe that there is a much better understanding, an acceptance that this is a real disease, and what the cause is of this disease, and that is much more embedded in society than before,” said Peter Graaff, head of Ebola operations at the WHO’s headquarters in Geneva.

Mohammed Kamara, who lives in Monrovia, lost two relatives and a friend to Ebola in 2014. “I know exactly what it means to have the disease in the country,” he said.

“We must be grateful to God and then to the government and its partners for the country to be declared free of Ebola. I only hope that it is the last time that we experience Ebola.”

(Additional reporting by Keiran Guilbert, Stephanie Nebehay, Tom Miles, Emma Farge, Matt Mpoke Bigg, Kate Kelland and Ben Hirschler; Writing by Edward McAllister; Editing by Jeremy Gaunt and Pravin Char)