What is the Zika virus?
The Zika virus is actually an arbovirus (a large group of viruses), transmitted by the bite of the Aedes aegypti mosquito, which is also the cause of the dengue fever. Zika was first identified in Brazil in April 2015. The virus received the same designation of the place of origin of its identification in 1947, after being detected in sentinel monkeys that were being used to monitor for the presence of yellow fever in the Zika forest in Uganda.
– What are the symptoms?
About 80% of people infected by the Zika virus do not develop clinical manifestations, whether they are adults or children. The main symptoms are headache, low-grade fever, mild joint pain, skin rashes, itching and redness in the eyes. Other, less frequent symptoms are swelling in the body, sore throat, coughing and vomiting. Overall, the evolution of the disease is benign and the symptoms disappear spontaneously after 3-7 days. However, joint pain may persist for approximately one month. Severe and atypical forms are rare, but when they occur they may exceptionally lead to death, as identified in November 2015 for the first time in history.
– How is the virus transmitted?
The most frequent mode of transmission is through the bite of the Aedes aegypti mosquito. Other possible forms of transmission of the Zika virus need to be examined in depth based on further scientific studies. There is no evidence of Zika virus transmission through breast milk, as well through urine, saliva or semen.
– Is there a vaccine against Zika?
There is no vaccine against the Zika virus. The development of vaccines against the Zika virus is part of Brazil’s National Plan Against the Aedes aegypti and its related investments. As this requires time for research to be conducted, however, it is essential that prevention and control measures against Aedes aegypti are adopted, because as well as combating Zika they will also help avoid other diseases such as dengue and chikungunya.
– What is the treatment?
There is no specific treatment for Zika viral infection. The recommended treatment for symptomatic cases consists of acetaminophen (paracetamol) or dipyrone to control fever and reduce pain. If an itchy rash occurs, antihistamines might be considered.
The use of aspirin and other anti-inflammatory drugs is not recommended, due to the increased risk of bleeding complications associated with infections caused by other flaviviruses.
– What precautions should be taken?
* Install mosquito nets on windows and doors, wear long-sleeved clothing – pants and shirts – and apply insect repellent on exposed areas of the body.
* It is advisable to stay in places where mosquito nets or other barriers available.
* If you notice the presence of skin rashes, red eyes or fever, seek health care.
* Do not take medication or attempt any treatment on your own before consulting a doctor.
* Seek medical advice on birth control and contraceptive methods.
– How is Zika virus diagnosed?
In most suspected cases of dengue, chikungunya and Zika, confirmation is made by clinical and epidemiological criteria. In the case of Zika, commercial serological diagnosis is not available yet. The test chosen to help in identifying areas of transmission of such diseases and in framing control measures is called RT-PCR, and is performed by laboratories of reference within Brazil´s Unified Health System (SUS) network. After the confirmation of one case in a particular area, other infections can be clinically diagnosed, through medical assessment of symptoms, and through the medical protocols currently used for dengue and chikungunya.
– What other types of tests are currently under development, and where?
The Evandro Chagas Institute is developing a serological test. Due to Brazil’s specific circumstances with regard to the circulation of other flaviviruses, which causes many serological cross-reactions, the test is recommended with certain reservations and is being made available to “sentinel” laboratories for the purpose of Zika diagnosis in Brazil. In addition to the serological test, the Institute has also carried out the complete genetic sequencing of the Zika virus circulating in Brazil.
– How do these tests contribute to further research and development?
The complete genetic sequencing of the Zika strains isolated from febrile patients will significantly contribute to the understanding of various aspects of the virus. Particularly significant was the detection of the Zika genome in two cases resulting in deaths, which enabled the international scientific community to envision an as-yet-undescribed evolution of Zika infections, a possible subject for future scientific studies.
– Are there any reports of Zika virus outbreaks in other countries?
Zika is considered endemic, though not widespread, in East and West Africa. And serological evidence in humans suggests the virus has been spreading in Asia since 1966.
According to the Pan American Health Organization/World Health Organization’s latest epidemiological bulletin, 22 countries/territories in the Americas have detected the indigenous transmission of the Zika virus (American Virgin Islands, Barbados, Bolivia, Brazil, Colombia, Dominican Republic, Ecuador, El Salvador, French Guiana, Guadalupe, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, St. Martin, Suriname and Venezuela).
ZIKA VIRUS AND
– What is microcephaly?
Microcephaly is a congenital malformation in which the brain does not develop properly. Babies with microcephaly are born with a head circumference which is smaller than normal. (The normal circumference is at least 32cm.) This congenital malformation can result from a number of different factors, including infectious chemical and biological substances, bacteria, viruses, and radiation.
– Is there confirmation that the increase in cases of microcephaly in Brazil is due to the zika virus?
When the Oswaldo Cruz Institute in Brazil detected Zika in the amniotic fluid of two pregnant women whose fetuses had microcephaly, and later the Evandro Chagas Institute identified the virus in a newborn baby with microcephaly (a fatal case), it was able to scientifically establish a connection between the Zika virus and the microcephaly cases currently being observed in Brazil.
– During what stage of pregnancy is there the greatest susceptibility to the virus?
In the cases reported so far, most of the pregnant women whose babies have developed microcephaly did themselves display symptoms of the Zika virus – mainly in the first three months of pregnancy. But women should be careful not to come into contact with the Aedes aegypti mosquito at any time during pregnancy.
– What are the Brazilian Ministry of Health’s current recommendations for pregnant women?
The Brazilian Ministry of Health emphasizes that pregnant women should not use any drugs that are not prescribed by a healthcare professional, that they should undergo all the required prenatal examinations, and that they should inform a healthcare professional of any alteration they perceive during pregnancy. It is also important that they take measures to avoid contact with the Aedes aegypti mosquito, for example by using insect repellents that are suitable during pregnancy, wearing long sleeves, and being careful not to let stagnant water accumulate anywhere in their home or workplace. Also, pregnant women should consult their doctor prior to traveling, whatever the destination.
– How is the diagnosis for microcephaly carried out? Is it possible to detect microcephaly during prenatal exams?
In Brazil, an initial physical examination of newborn babies is routine, and should be carried out within 24 hours of birth. This is one of the key moments to carry out an active search for possible congenital anomalies. It is also possible to diagnose microcephaly during prenatal exams. However, pregnant women should ask their physician about the medical imaging modality recommended to their case.
– What is the treatment for microcephaly?
There is no specific treatment for microcephaly. There are support procedures that can assist in the development of the baby and the child, and Brazil´s Unified Health System (SUS) network recommends these procedures. As each child with microcephaly may develop different complications – including respiratory, neurological and motor complications – medical specialists in a number of different areas might become involved. Recommended services include primary care, specialized rehabilitation, examinations and diagnosis, hospital services, and also orthotics and prosthetics in applicable cases.
– Can microcephaly kill or cause serious consequences?
In about 90% of cases, microcephaly is associated with intellectual disability (the exceptions are when the condition is inherited, in which case the baby’s cognitive development can be normal). The type and severity of the sequelae vary from case to case. A connection has already been identified between infection by the Zika virus and severe cases of microcephaly, including those leading to death. In these serious cases, the Zika virus RNA was identified while other known viruses such as dengue and chikungunya were found to be absent.
– Can children and babies
affected by the Zika virus experience neurological problems?
It is fundamental to avoid rumors and speculations. There are no documented cases of sequelae in children who contracted Zika after they were born. Microcephaly is a condition identified only at birth. People of any age can be infected by the virus, not only children.
– Which Brazilian states are recording higher than average numbers of microcephaly cases?
Brazil’s Ministry of Health investigates 3.488 suspected microcephaly cases throughout the country. A report published on January 27 shows that 270 cases have been confirmed as microcephaly, six of which related to the Zika virus. 462 reported cases have been dismissed. By January 23, 4.180 suspected microcephaly cases have been reported.
According to that report, cases have been registered in 830 cities throughout 24 Brazilian States. The Northeast region concentrates 86% of the reported cases, Pernambuco being the State with the largest number of cases which remain under investigation (1.125), followed by the States of Paraíba (497), Bahia (471), Ceará (218), Sergipe (172), Alagoas (158), Rio Grande do Norte (133), Rio de Janeiro (122) and Maranhão (119).