Virus isolated in Uganda
Zika virus is first isolated from a sentinel rhesus monkey placed in a cage on a tree platform in the Zika Forest near Lake Victoria, Uganda. The monkey, Rhesus 766, was part of the Rockefeller Foundation’s program for research on jungle yellow fever. Two days later, Rhesus 766, still febrile, was brought to the Foundation’s laboratory at Entebbe and its serum was inoculated into mice. After 10 days all mice that were inoculated intracerebrally were sick, and a filterable transmissible agent, later named Zika virus, was isolated from the mouse brains.
Virus found in mosquitos
A second isolation of the virus from the mosquito Aedes africanus is confirmed in Uganda, at the previous site.
Mosquito transmission discovered
Transmission of the virus by artificially fed Ae. aegypti mosquitoes to mice and a monkey in a laboratory is reported.
First well-documented infection report
The first well-documented report of human Zika infection is reported, when researcher D.I.H. Simpson describes his own occupationally acquired illness at age 28. The infection starts with mild headache. The next day, a rash covers his face, neck, trunk, and upper arms, and spreads to his palms and soles. Transient fever, malaise, and back pain develops. By the evening of the second day of illness the fever abates, the rash fades, and he feels better. By day three, he feels well and only the rash remains, which disappeared over the next two days. The virus is isolated from serum collected while he has the fever.
Seven people are reported with Zika virus in Indonesia. A subsequent study indicates that 9/71 (13%) human volunteers in Lombok, Indonesia, have a neutralizing antibody to the virus. Symptoms include fever, anorexia, diarrhea, constipation, abdominal pain, and dizziness.
An outbreak of illness characterized by rash, arthralgia, and conjunctivitis is reported on Yap Island in the Federated States of Micronesia. Serum samples from patients in the acute phase of illness contained RNA of Zika virus. This is the first time Zika has spread outside its usual geographic range. Symptoms noticed are: rash, conjunctivitis, and arthralgia (joint pain).
French Polynesia outbreak
The Zika virus races through the many islands of French Polynesia, including Tahiti and Bora Bora. In early 2014, it moves to the Cook Islands, just to the west, and New Caledonia, close to Australia. It also leapt to Easter Island, home of the giant stone heads, officially arrival in the Western Hemisphere.
First New York case0 Comments
The first case of Zika infection detected in New York City is found in a 48-year-old traveler who lives near Central Park. He had just returned from a long trek through Ecuador, Peru, Bolivia, Chile, Easter Island and Hawaii, with a stopover in French Polynesia. The nurse who first saw him, said he pulled his shirt out of his bluejeans and peeled it off, exposing a pinkish rash he said he had had for 11 days:
I took one look and said, ‘Dengue fever. He said, ‘I’m not so sure. I think it’s Zika.’ I’d heard of Zika, but nobody was thinking about Zika. But this is a very, very bright guy. He travels a lot, he knows about safe water and safe altitudes for malaria. He was right on the money, that guy. In Polynesia, he had read articles in the local paper about Zika.
She takes a blood sample and again 20 days later, and sends both samples to the Centers for Disease Control and Prevention in Atlanta. Their tests showed that he had antibodies to dengue, West Nile and Zika, but the count of Zika antibodies had shot up. The nurse says her patient had found an article about a scientist in Colorado who had infected his wife with the virus after returning from Africa.
Because of that paper, I advised him not to have unprotected sex with his common-law wife. What’s weirder…He knew there were cases of Guillain-Barré connected to it.
Guillain-Barré is a form of temporary paralysis that starts in the hands and feet. If it reaches the lungs the patient can die.
Virus spreads in Brazil
Shortly after the 2014 World Cup, doctors start to notice patients trickling into public hospitals in Natal, capital of the state of Rio Grande do Norte, about 200 miles up the coast from Recife. Natal had been one of the host cities of the soccer championship, which draws fans from all over the world. A second theory, proposed by French scientists, who had investigated the outbreak in Polynesia, was that it arrived a few weeks later, during the Va’a World Sprint, a canoe race in Rio that attracted teams from several Polynesian islands. Almost all victims had the same symptoms: a flat pinkish rash, bloodshot eyes, fever, joint pain and headaches. None were desperately ill, but the similarities were striking. Local epidemiologist:
That scared some patients and doctors, and my team. We knew nothing other than that it might be some kind of light dengue.
In January, 100 infected people show up at the state’s hospitals in one day. Infectious disease specialist:
We alerted the federal authorities that we were dealing with something urgent and new. But their reaction was sluggish.
By March 2015 the virus appears in two more Brazilian states, then reaches Salvador, a city of 2.5 million. Doctors speculate that the symptoms are the result of an allergy; that it was roseola, a childhood illness; that it was a new variant of Fifth Disease, a facial rash that gives children a “slapped-cheek” look. Dr Soares, a biologist:
People were claiming it was polluted water. I began thinking it was something transmitted by mosquitoes.
Working in his modest lab with a colleague, Dr. Soares tests thousands blood samples. Other doctors are doing the same. Over 6,800 samples are tested from victims ranging from 4 months to 98 years old. Parvovirus, dengue, chikungunya and other suspects are all ruled out, leaving Zika as the cause in April. Dr Soares:
I actually felt a sense of relief. The literature said it was much less aggressive than viruses we already deal with in Brazil.
Link to Zika confirmed, officials downplay
The Oswaldo Cruz Foundation confirms Dr Soare’s research. Officials downplay the disease as having moderate effects, compared to Dengue fever, which kills hundreds people each year. Health Minister:
Zika virus doesn’t worry us. It’s a benign disease.
2700 microcephalic babies born in 2015
The New York Times reports that more than 2700 microcephalic babies have been born in Brazil in 2015, up from fewer than 150 in 2014, according to news media reports in Brazil. Though the increase is tentatively blamed on spreading Zika virus, some say the link is not clear.
First US case from Brazil outbreak
The CDC says a traveler in Houston from Latin America, is diagnosed with Zika, the first diagnosis in the United States since an outbreak began in Latin America.
First brain-damaged baby in US
The Hawaii State Department of Health says a baby born with an unusually small head and brain in an Oahu hospital had been infected with the Zika virus. The presence of the virus was confirmed by the CDC. The child’s mother was probably infected early in her pregnancy by a mosquito when she lived in Brazil in May in 2015. The virus presumably reached the embryo and damaged its developing brain. Hawaii’s state epidemiologist:
We are saddened by the events that have affected this mother and her newborn. This case further emphasizes the importance of the C.D.C. travel recommendations released today.
Virus likely to spread across Americas
The WHO warns that the Zika virus is likely to spread across the Americas. The virus has already been found in 21 countries in the Caribbean, North and South America. No treatment or vaccine is available. The virus is spread through the Aedes mosquito. This mosquito is found throughout the Americas with the exceptions of Canada and Chile. 80% of infections do not show symptoms, but there seems to be a link between the virus and impaired fetal development.
Countries warn women to delay pregnancy
Officials in four Latin American and Caribbean countries warn women to delay pregnancy as the consequences of the Zika virus outbreak for developing fetuses become more apparent. During an outbreak of the Zika virus in Brazil, the nation saw an increase of nearly 4,000 infants born with microcephaly. US health authorities have warned pregnant women to avoid travelling to more than 20 countries in the Americas and beyond, where Zika cases have been registered. Colombian health minister:
We are doing this because I believe it’s a good way to communicate the risk, to tell people that there could be serious consequences.
First US transmission case; through sexual contact
The first known case of Zika virus transmission in the United States is reported in Dallas, TX. Officials say it was likely was contracted through sex and not a mosquito bite. The person was infected through sexual contact with someone who had traveled to Venezuela. Texas Department of State Health Services:
Case details are being evaluated, but the possibility of sexual transmission from an infected person to a non-infected person is likely in this case.
Drugmakers announce virus efforts
Sanofi announces that it has launched a project to develop a vaccine against the virus, the most decisive commitment yet by a major vaccine maker. The company says its Sanofi Pasteur vaccines division would use its expertise in developing vaccines for similar viruses such as yellow fever, Japanese encephalitis and dengue. The University of South Australia also says it is working on a Zika vaccine with Australian biotech Sementis Ltd. U.S. drug developer NewLink Genetics Corp said it has started a project to develop Zika treatment options.
Asks blood donors to wait 28 days
The American Red Cross asks prospective donors who have visited Mexico, the Caribbean, or Central or South America during the past four weeks to wait at least 28 days before giving blood. The organization says:
The risk of transmission through blood donation continues to be extremely low in the continental U.S.
Declares State of Emergency in FL counties with Zika virus
Gov. Scott declares a state of emergency in the four counties where people have been diagnosed with the Zika virus: Miami-Dade, Hillsborough, Lee and Santa Rosa. Nine people have been diagnosed with Zika in Florida, though health officials believe that all of them contracted the disease outside of the U.S. Scott’s executive order requires the state health officer to “take any action necessary to protect public health” and allows the commissioner of agriculture to issue a “mosquito declaration” in the affected counties to reduce populations of the insects that can spread the disease. Scott:
Although Florida’s current nine Zika cases were travel-related, we have to ensure Florida is prepared and stays ahead of the spread of the Zika virus in our state.