The most important information about ZIKA virus and its diagnostics at the National Institute of Public Health-NIH
Zika virus belongs to the Flaviviridae family, genus Flavivirus which includes about 65 different, genetically and antigenically related viruses.
- Vector, in which the Zika virus multiplies are arthropods mosquitoes of genus Aedes. They are also vectors for other viruses such as, for example, yellow fever virus, Dengue virus, Chikungunya virus, West Nile virus and others. Arthropods transmit the infection to the vertebrates.
Mosquito Aedes aegypti occurs in tropical and subtropical regions and is a vector for yellow fever virus, Dengue, Chikungunya, and others. In Europe, the mosquito occurs mainly on the Black Sea coast.
The second mosquito, Aedes albopictus, named Asian or tiger mosquito, is a vector for about 20 arboviruses, including yellow fever virus, Dengue virus, Chikungunya virus, West Nile virus, the virus of Japanese encephalitis type B, viruses of Eastern, Western and Venezuelan equine encephalitis. The mosquito is quite resistant to low temperatures – in Japan it was observed in areas of + 12 ° C isothermal line.
In the twentieth century, the expansion of the mosquitoes was observed throughout the world, and in the 70s also in Europe, on the Mediterranean coast.
Distribution maps of Aedes aegypti and Aedes albopictus mosquitoes can be found at ECDC webpages:
- Distribution of Zika virus:
- identified in 1947 in Uganda;
- from 2006 can be found in Africa and South-East Asia;
- in 2007 outbreak on Yap Island, then expansion to other Pacific islands;
- in 2015 virus was reported in South America;
- Key Facts:
- The incubation period ranges between approximately 3 to 12 days after the bite of an infected mosquito;
- Most of the infections remain asymptomatic (approximately 60-80%);
- The symptoms of Zika virus disease can include: mild fever, skin rashes, conjunctivitis, muscle and joint pain, malaise or headache. These symptoms normally last for 2-7 days.
- There is no specific treatment or vaccine currently available.
- The best form of prevention is protection against mosquito bites.
- Infection of foetus – if infection happens during pregnancy, it may be transmitted to the foetus. The latest data confirms the possibility of foetus infection by Zika virus. The virus genom was detected in foetal waters. Congenital malformations as microcephaly in newborns were notified during recent Zika disease outbreaks (French Polynesia and Brazil). In Brazil more than 4000 cases of microcephaly were recorded, which represents a 10-fold increase in comparison to previous years, when Zika virus infections weren’t observed;
- Unusual increases of Guillain–Barré syndrome were reported in several countries in Americas and French Polynesia coinciding with Zika virus outbreak;
- There is a potential risk of Zika virus transmission from blood transfusion and sexual contact (virus is present in semen for 3 weeks – longer than in blood);
In Poland blood donors are interviewed before each blood donation due to safety measures. A donor returning from countries with probable exposure to Zika virus is asked to report herself/himself later on.
- Diagnostics of Zika virus infections:
Polymerase chain reaction (PCR)*:
- In blood – only in the first few days up to 7th. day. It means, that in case of long period of incubation (12 days), even on the first day of symptoms of disease, virus can’t be found in blood.
- In urine and semen – virus might be present for 3 weeks and at this time it may be detected.
* at the moment at NIPH-NIH work is under way to introduce PCR test detecting ZIKA virus
- Blood sample collected not earlier than after 7-10 days, since the infection;
- IgM and IgG antibodies against Zika virus are detected;
- Serological results are sometimes difficult to interpret due to cross reactions in flaviviruses. It is a very important problem in Poland due to endemic occurrence of another flavivirus – tick born encephalitis virus (TBV);
- The most specific results one receives when antibodies against virus’s NS1 antigen are detected
We offer the possibility of examination of serum samples for antibodies against Zika virus NS1 protein (in both class of immunoglobulins: IgG and IgM) as well as serological tests against Dengue virus NS1 protein.
Laboratory testing is performed only during working hours of NIPH-NIH,
from Monday to Friday (8.00am – 3.35 pm)
Serum sample: at least 1 ml of serum obtained by collection of 3-5 ml of blood and centrifugation should be sent to:
National Institute of Public Health – National Institute of Hygiene
Department of Virology
Chocimska 24 Str.
Transportation of serum samples might be conducted at room temperature (18-25°C) by regular post, after packing following the guideline. If fresh blood is sent – sample cannot be frozen, and sample must be delivered within 24 hours.
Every biological specimens sent to any examination in NIPH-NIH must be packed and described following the guidelines at: http://www.pzh.gov.pl/nasza-oferta/badania-diagnostyczne/.
The price of ELISA test is 510 zł (both IgM and IgG against Zika virus).
Payment by bank transfer:
Bank PKO BP S.A. account number 98 1020 1042 0000 8302 0200 8027
Narodowy Instytut Zdrowia Publicznego – Państwowy Zakład Higieny
- Chocimska 24
Please write your name and surname and name of a diagnostic test (e.g. Anna Kowalska – examination of Zika virus infection)