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Zika: Two Billion at Risk in Africa and Asia, Study Says

Zika: Two Billion at Risk in Africa and Asia, Study Says

More than two billion people could be at risk from Zika virus outbreaks in parts of Africa and Asia, according to scientists writing in The Lancet Infectious Diseases. Populations in India, Indonesia and Nigeria are some of the most vulnerable to transmission, the researchers said. They used data on air traveller numbers to help model their predictions. However, they acknowledge that immunity to the virus could already exist in some areas and could reduce the risk. The research team, from the London School of Hygiene and Tropical Medicine, Oxford University and the University of Toronto, Canada, said “vast numbers” of people were living in environments where it would be hard to prevent, detect and respond to the virus. They looked at factors such as the numbers of people who travelled from Zika-affected areas in South America to Africa and Asia, the presence of mosquitoes that can pass on the virus, and the climate in the regions to assess which countries could be most at risk from an outbreak. In their study, the researchers suggest that the Philippines, Vietnam, Pakistan and Bangladesh could be particularly vulnerable to a Zika outbreak because of their limited health resources. Dr Kamran Khan, study author from St Michael’s Hospital in Toronto, said: “The impact on populations will also depend heavily on the country’s ability to diagnose and respond to a possible outbreak.” And he added: “Our findings could offer valuable information to support time-sensitive public health decision-making at local, national, and international levels.” Zika spread More than 65 countries and territories now have continuing Zika transmission. The infection, spread by mosquito bites, reached Africa...
Zika Infection may Be Masked by Other Viral Infections

Zika Infection may Be Masked by Other Viral Infections

Symptoms of infection with the Zika virus in Brazil may be masked by simultaneous infection with other mosquito-spread viruses common in the same region—such as dengue fever and chikungunya viruses—pointing to the need for comprehensive testing, according to a study led by a UCSF expert in DNA-based diagnostics in collaboration with Brazilian researchers. Using sophisticated genetic fingerprinting techniques that can identify multiple co-infections, a research team led by Charles Chiu, MD, PhD, associate professor of laboratory medicine and of medicine, and director of the UCSF-Abbott Viral Diagnostics and Discovery Center at UCSF, found two cases of co-infection with the chikungunya virus among 15 previously confirmed Zika cases from the state of Bahia, Brazil, diagnosed from April 2015 to January 2016. “With these viruses, the symptoms associated with acute illness, including fever, rash, joint pains and conjunctivitis, are non-specific, so it is difficult to make an accurate diagnosis based on clinical findings alone,” Chiu said. “It’s easy to imagine a physician failing to detect Zika when they instead suspect a different virus that causes similar symptoms, and then their suspicion is confirmed by a diagnostic test designed to detect only that virus – they might easily miss a co-infection if they do not test for more than one virus.” Curtailing an Outbreak In most cases of infection, Zika itself causes no symptoms or relatively minor symptoms. In a collaboration with Silvia Sardi, PhD, of the Federal University of Bahia, one of the first scientists to identify Zika as the cause of the Brazilian outbreak, Chiu used a single “metagenomic” laboratory test that can detect virtually any known virus to analyze...

Prenatal brain MRI of fetuses with Zika virus infection.

Abstract BACKGROUND: An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. OBJECTIVE: To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. MATERIALS AND METHODS: We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. RESULTS: Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). CONCLUSION: Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus...
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