In a boost to the global battle against Zika virus, Google today announced that it is helping build a mapping platform to help predict outbreaks and has put $1 million toward UNICEF response efforts in Latin America.
In other developments, clinicians from Martinique today reported that Zika virus seems to persist longer in urine than in blood, based on their work-up of two recent Guillain-Barre syndrome (GBS) cases, and health departments reported new cases in pregnant women and instances of sexual transmission of Zika.
Also, Brazil reported more than 200 more suspected microcephaly cases and results of lab experiments with the virus on common Culex mosquitoes, while the Food and Drug Administration (FDA) released guidance on screening of cells, tissue, and other biological products such as semen.
Google response steps
In a blog post today, Google said unlike other outbreaks, the spread of Zika virus is proving harder to map and contain. But it added that, given the company's experience analyzing large sets of data, it is in a good position to help.
Google said a volunteer team of its engineers, designers, and data scientists are helping the United Nations Children's Fund (UNICEF) build a platform to analyze data from different sources, such as weather and travel patterns.
The goal of the open-source tool is to help identify Zika transmission risks for different regions and to help UNICEF, as well as governments and other groups, gauge where to target its efforts and resources. It said the platform could other be modified for use in other global emergencies.
Google also said it has donated $1 million to UNICEF response efforts in Latin America, with up to $500,000 more in a company employee fund-matching campaign. The company also added more extensive information about the virus on its search engine in 16 different languages.
Cases hint at genitourinary virus persistence
In their investigations of GBS in two patients with suspected Zika virus infections, clinicians and lab experts in Martinique found evidence of viral excretion in urine that lasted longer than 15 days and at a time when blood tests were negative for viral RNA. They reported their findings in today's issue of Eurosurveillance.
The two GBS cases were reported in January, not long after Martinique noted its first Zika virus cases. Both patients—one a young adult and the other in his or her 50s—were admitted to the hospital after experiencing gait disturbances. Neither had a history of a recent arboviral infection, and both needed mechanical ventilation while hospitalized.
Blood tests for possible infectious triggers of GBS, including Zika virus, were negative, and serology tests for Zika virus are pending. However, Zika virus was detected in urine by reverse-transcriptase polymerase chain reaction (RT-PCR) testing on day 15 after neurologic symptom onset in the younger patient and at 5, 15, and 21 days after GBS symptom onset in the older patient.
The authors noted that other reports have suggested that for other flaviviruses, RNA is detected in urine at higher loads and for a longer time than in plasma, which may be helpful for diagnosing the infections.
Researchers cautioned that the asymptomatic prolonged Zika virus excretion may not be related to the neurologic symptoms and that the pathophysiologic mechanisms need to be further explored. They concluded, however, that urinary excretion of the virus should be followed for longer than 15 days after GBS symptoms onset and that it's possible that the genitourinary tract is a sanctuary for persistent viral replication.
Zika in pregnancy, sexual transmission
In California, the Napa County Public Health Division yesterday announced that state lab health officials have confirmed a Zika virus infection in a pregnant county resident who had traveled to Central America, according to an announcement on the department's Facebook page.
Few other details were available, other than that the woman is not currently symptomatic. The announcement didn't say what trimester the woman was in when the Zika infection occurred.
Last week the US Centers for Disease Control and Prevention (CDC) released an investigation report on Zika virus in 9 pregnant women, and it said it was also looking into 10 more reports in pregnant travelers.
Elsewhere, New Zealand's health ministry said it is investigating a possible sexual transmission case, Radio New Zealand reported today. It said a man who got sick after visiting a country where local transmission is occurring has tested positive for the virus, as has his female partner who had not traveled to an affected country.
A ministry official said the woman could have contracted the virus from unprotected sex or from being bitten by a mosquito brought into the country by her partner's luggage.
More microcephaly in Brazil
Brazil's health ministry yesterday reported 269 more suspected microcephaly cases and has ruled out 96 earlier ones, putting the total number of cases to investigate at 4,222, according to a statement translated and posted by Avian Flu Diary, an infectious disease news blog. Microcephaly, a suspected complication of maternal infections, involves babies born with smaller-than-normal heads and underdeveloped brains.
According to the health ministry's latest totals, it has confirmed 58 more cases since last week, bringing that total to 641.
Over the course of the outbreak 5,909 suspected cases have been reported, with 1,046 of them ruled out.
Zika in Culex mosquitoes
In another Brazilian development, researchers from the Fiocruz Institute that the virus has been found in salivary glands of Culex mosquitoes that were experimentally infected, according to a Brazilian media report.
Researchers presented the preliminary findings during a workshop in the city of Recife. They said it's not clear if the Culex mosquitoes can transmit the virus to people, but the lab findings are concerning, because that mosquito species is commonly found in many parts of the world. Currently, Aedes aegypti mosquitoes are thought to be the primary vector.
Guidance on tissue and cell donors
Finally, the FDA on Mar 1 issued guidance on preventing Zika transmission from donated human cells, tissues, cellular and tissue-based products. The items include reproductive tissues such as semen and oocytes.
The general donor deferral period for people who were sick with Zika virus, were in an active transmission area, or had sex with a man who may have been exposed to the virus is 6 months to account for uncertainty about how long the virus can persist in tissues, especially since it has been known to persist in semen for up to 10 weeks after symptom onset.
Mar 3 Google blog post
Mar 3 Eurosurveill report
Napa County Public Health Division Facebook page
Mar 3 Radio New Zealand report
Mar 2 Avian Flu Diary post
Mar 3 Globo.com report (in Portuguese)
Mar 1 FDA press release