Zika virus: Will it spread to Europe and Germany soon?
Zika virus particles (red)
The Zika virus, which is transmitted by the mosquito species Aedes aegypti, is currently spreading rapidly in South America, particularly in Brazil. The virus may damage unborn foetuses during pregnancy and cause brain malformations. Up to now, there has been no vaccine available; programs to destroy the mosquitos have been initiated. Could the virus soon spread to Europe and how high is the risk of infection at the upcoming Olympic Games in Rio de Janeiro? An expert from the German Center for Infection Research (DZIF), Prof Jan Felix Drexler, University of Bonn, evaluates the situation and calls for more research and less fear-mongering.
How high is the risk of the Zika virus emerging and spreading in Europe and Germany soon?
J.F. Drexler: There have already been imported cases in Europe, and people will also bring the virus to Europe and Germany in future. However, the chances of the virus spreading further through mosquitoes here is extremely low. The mosquito (Aedes aegypti) which transmits the virus in South America does not exist here. It has not been clarified yet whether the Asian tiger mosquito (Aedes albopictus), which is also found in Germany, can transmit the virus. In any case, their existing numbers are too low for the Zika virus to spread in Germany.
Can pregnant women currently travel to South America? How likely is there a link between the Zika virus and malformations in newborns?
J.F. Drexler: A connection between Zika virus infections and direct foetal damage has not yet been confirmed. Many aspects of the infection have not yet been understood. Zika viruses have been known for a long time and did not cause remarkable rates of “microcephaly” in earlier outbreaks. Microcephaly is the malformation which has recently been observed in connection with Zika virus infections in a number of cases. According to verbal reports from Brazilian colleagues, not all sectors of the population have been affected by microcephaly. Pregnant women should therefore be informed of the risks, but we believe that the risk of infection with Zika viruses when travelling, and consequently getting an ill child, is low. However, the potential foetal damage is a specific issue which calls for research in this field.
Do special precautions need to be taken for the upcoming Summer Olympic Games in Brazil in August?
J.F. Drexler: We suspect that the problem will be more contained by then. As opposed to dengue virus infections, humans can only get infected with Zika viruses once in their lifetime and subsequently become immune. It currently looks like we will experience a phase of massive spread of the virus which, in turn, will result in immunity in the population through which the epidemic will self-contain. Additionally, we must remember that the virus is not particularly virulent. The symptoms are not life-threatening.
Are Zika viruses being researched in Germany?
J.F. Drexler: In Bonn, we are already working on testing systems, and at other DZIF partner sites, for example in Hamburg, scientists are working on the Zika virus as well. One of the most important goals should be to develop a vaccine. At the DZIF, we are very well equipped for this kind of research on emerging infections.
Background
Zika virus
The Zika virus causes fever, rashes, joint pain and conjunctivitis. The virus can be transmitted to the foetus during pregnancy. Researchers suspect that there is a link between the viral infection and brain malformations in babies: since October, over 3500 cases of babies and foetuses with microcephaly, an abnormally small head, have been registered in Brazil. However, many of these cases have not yet been fully investigated, and Zika infections have only been confirmed in only a small number of cases. According to the current state of knowledge, it is transmitted by the mosquito species Aedes aegypti—a type of mosquito which does not exist in Germany. Aedes albopictus, a species which is rare in Germany, could theoretically transmit the virus—but these insects are so small in number that experts believe the chances of the virus spreading here are extremely low. The virus was described for the first time in Uganda almost 40 years ago. It is suspected that the virus was brought to Brazil by numerous visitors during the 2014 football World Cup.
Virus research at the DZIF
The DZIF research field “Emerging Infections” has put in place an excellent foundation to enable rapid development of diagnostic agents and vaccines in the event of novel virus outbreaks, and to prevent further spreading of outbreaks. Christian Drosten’s research team in Bonn has already developed a standard test for the MERS pathogen which is being used globally. DZIF scientists in Marburg and Hamburg are involved in Ebola research.
You can find further Information on the Zika virus at the Robert Koch Institute