zika

A single genetic glitch may explain how Zika became so dangerous

A single genetic change that occurred in 2013 may explain how Zika acquired the ability to attack fetal nerve cells, causing a severe birth defect in babies whose mothers were infected while pregnant, Chinese and U.S. researchers reported on Thursday.

Scientists have posited many theories about why Zika, a mosquito-borne virus that had been linked with only mild symptoms since its discovery in 1947, could suddenly be associated with thousands of cases of the birth defect known as microcephaly, as it was in Brazil in 2015.

That outbreak prompted the World Health Organization to declare Zika a public health emergency in 2016, and set off a scientific quest to determine whether Zika could cause microcephaly, a condition marked by small head size.

Several teams have already traced the virus circulating in Brazil and elsewhere in South America to a strain of Zika that had been quietly circulating in Southeast Asia for decades.

In the new study, published in Science, Ling Yuan of the Chinese Academy of Sciences and colleagues compared genetic changes in samples of the South American virus with one isolated in 2010 in Cambodia.

They created seven sample viruses, each with a single genetic difference from the Cambodian strain, and tested these in brains of fetal mice. Although the viruses caused some degree of damage in all, those infected with a virus that carried a single mutation in a structural protein called prM developed severe microcephaly. That strain also proved more lethal to fetal brain cells.

The team estimates the genetic change occurred in May 2013, just before a French Polynesian outbreak of Zika in which the first cases of microcephaly and Guillain-Barre, a rare neurological disorder, were noted.

“Our findings offer an explanation for the unexpected causal link of Zika to microcephaly, and will help understand how Zika evolved from an innocuous mosquito-borne virus to a congenital pathogen with global impact,” Yuan and colleagues wrote.

One study author, Dr. Pei-Yong Shi of the University of Texas Medical Branch in Galveston, Texas, said other mutations also fueled the explosive epidemic, including one he and others reported on in May in the journal Nature that enhanced Zika’s ability to infect Aedes aegypti mosquitoes, which carry the virus.

Last November, WHO pronounced Zika no longer an international emergency, but stressed that the virus, found in at least 60 countries, will keep spreading where mosquitoes that carry Zika are present.

Related: Zika Virus could be the next cure for brain cancer, What you need to know about Dengue, Zika and Chikungunya this rainy season

Reporting by Julie Steenhuysen; editing by Susan Thomas

A single genetic change that occurred in 2013 may explain how Zika acquired the ability to attack fetal nerve cells, causing a severe birth defect . . .

Follow Us On Google News | Get Our Newsletter



Trending News on PVDN

  • Where do foreigners come from and where do they live in MexicoMexico City Protest on July 5 Challenges Gentrification and Airbnb’s Impact on Housing Residents of Roma and Condesa will gather at Parque México on July 5 to protest gentrification, rising rents, and Airbnb’s effect on local housing. This Saturday, July 5, Mexico City will witness its first organized citizen protest against gentrification—a peaceful but urgent gathering taking place at 3:30 p.m. at the Lindbergh Forum in Parque México,…
  • raw-sewage-playa-los-muertos-puerto-vallartaMore Raw Sewage Dumping at Playa Los Muertos Appear to Come From Local Hotel Business owners in Puerto Vallarta are demanding action after raw sewage was discovered leaking onto Playa Los Muertos, raising public health and tourism concerns. A raw sewage leak at Playa Los Muertos in Puerto Vallarta has sparked outrage among local tourist service providers and business owners, who say the contamination is driving away visitors and…
  • puerto-vallarta-rainfall-hurricane-flossie-july-2025Puerto Vallarta braces for torrential rains as Hurricane Flossie gains strength Puerto Vallarta faces a high risk of flooding as Hurricane Flossie intensifies in the Pacific. Torrential rains and overwhelmed drainage systems pose major challenges for the city. Puerto Vallarta, a city wedged between the Sierra Madre mountains and the Pacific Ocean, is no stranger to dramatic weather shifts—but this summer, the skies are testing the…
  • puerto vallarta lettersPuerto Vallarta needs a new image to create meaningful reasons for travelers to visit Business leaders at Jalisco Tourism Secretariat forums stressed the need for renewing Puerto Vallarta image and diversifying attractions to appeal to national and international markets. Local business leaders and tourism specialists agreed this week that Puerto Vallarta needs a fresh look and a broader range of attractions to compete at home and abroad. In a…
  • protests3Mexico City Protests: There is a fine line between anti-gentrification and xenophobia The line between anti-gentrification and racism is clear if you choose to see it: genuine activism targets policy and practice, not nationality or ethnicity. I have lived in Mexico for two decades, and I have never witnessed the level of anti-American sentiment that exists today. All of it is tied to the buzzword "gentrification," a…
  • José Luis Velázquez RodríguezSEAPAL Official Reported Missing in Puerto Vallarta Authorities in Puerto Vallarta have launched a search for José Luis Velázquez Rodríguez, SEAPAL's head of transparency, who has been missing since June 30. Family and officials are urging the public to report any information. Local authorities and civil protection units have launched a search operation for José Luis Velázquez Rodríguez, head of the Transparency…
  • puerto-vallarta-police-chase-bahia-de-banderasPuerto Vallarta police chase ends in deadly collision in Bahía de Banderas A Puerto Vallarta police chase along Highway 200 ended in a deadly collision in Bahía de Banderas, leaving two people dead. A high-speed chase that began in Puerto Vallarta, Jalisco, and ended in Bahía de Banderas, Nayarit, left at least two people dead and raised new questions about police engagement and road safety in the…
  • mexico city real estateGentrification in Mexico City is not the reason for the high cost of housing City housing shortage, not gentrification, drives prices skyward as planning lags behind demand and foreigner influence remains minimal. High real estate costs in Mexico City stem from a deep and persistent housing shortage—exacerbated by land constraints, tangled regulations and speculative investment—rather than by the presence of foreign residents. Despite headlines blaming “gentrification,” foreign-born residents make…
  • protestProtest graffiti and smashed windows mars anti-gentrification rally in Mexico City Residents and activists joined an anti-gentrification rally in Mexico Park, but the anti-gentrification rally Mexico Park turned destructive as masked youths defaced local shops and broke windows. A rally against gentrification held yesterday in Mexico City’s Parque México drew residents from Juárez, Roma, Condesa and Hipódromo alongside local activists. Organizers billed it as the city’s…
  • no-damage-jalisco-hurricane-flossieNo Damage Reported in Jalisco as Hurricane Flossie Moves Away While Mexico's Weather Service predicted heavy rains, Hurricane Flossie causes no damage along Jalisco’s coast. The Category 3 storm brings light rain and moderate waves as it moves away from the region. The coasts of Jalisco remain calm and largely unaffected following the passage of Hurricane Flossie, a powerful Category 3 storm that is now…
Scroll to Top