What are the symptoms of Zika virus in men and women?
The Zika virus infection is a virus that is transmitted by mosquitoes. To date, it has been active mainly in Africa, Southeast Asia and the Pacific Islands. Since 2015, the Zika virus is spreading rapidly in South American countries. Fever, joint pain and conjunctivitis are typical Zika virus symptoms. A Zika virus infection in pregnant women can pass to the child and damage the unborn child. However, even in the case of infected adult persons, possible serious consequences can occur.
Zika virus infection defitinon
A Zika virus infection causes a febrile infection (Zika fever). The causative agent, the Zika virus, is transmitted by mosquitoes of the Aedes genus to humans.
On average, every fourth to fifth typical Zika virus symptoms develop. The course is usually mild. However, infected pregnant women can transfer the pathogen to their unborn child. More cases were reported, especially in Brazil, where neonates of infected mothers had too small a head (microcephalus). In addition, a zika infection could cause the otherwise very rare Guillain-Barré syndrome – a disease of the nerve tracts, which can be associated with severe paralysis.
Spread of Zika virus infection
The Zika virus was discovered in 1947 by a rhesus monkey in the Zika forest of Uganda and named after it. The first Zika virus infections in a human were described in Uganda and Tanzania in 1952. In 2007, the first major outbreak occurred in the West Pacific Yap Islands (part of Micronesia). 75% of the local population fell ill with a Zika virus infection. A major outbreak followed this in 2013 in French Polynesia. Here about ten percent of the population fell.
In the meantime, the virus has spread more and more. International attention was given to the great Zika outbreak in Brazil in 2015, especially because the connection with microcephaly in children who are infected in the mother’s body.
In the meantime, the virus has spread rapidly over the South American continent, and is now being launched in Florida.
Travel warning for regions with Zika virus infection
Travelers are infected in the affected countries and bring the virus into the home where they can infect others, for example in sex. If there are no mosquitoes in the native country, the larger viruses are excluded.
For affected regions, health care providers are advocating travel warnings for pregnant women. In addition, tourists are increasingly protected from mosquito bites to prevent a Zika virus infection.
Zika virus infection symptoms
A Zika virus infection is often asymptomatic, that is to say: carriers of the pathogen do not show any symptoms of disease. If people suffer from a Zika virus infection, the disease is usually mild.
The first symptoms of Zika virus appear after about two to seven, sometimes only after twelve days (incubation period). The signs are similar to those of other viral diseases transmitted by mosquitoes, especially those of the Dengue or Chikungunya fever. For example, sufferers usually suffer from the following symptoms:
- Slight fever (“subfebrile” temperatures around 38 degrees Celsius)
- Nodular-spotted skin rash (maculo-papular exanthema)
- Joint pain (arthralgia)
- Reddened eyes by conjunctivitis (conjunctivitis)
Some patients feel very sick and also complain of headache and muscle pain. Dizziness, stomach aches, nausea with vomiting and diarrhea are also rarely reported. Severe illnesses, such as those occurring in dengue (bleeding due to massive platelet decay) or chikungunya (monthly joint pain, bleeding), are very rare.
However, some physicians presume a link between a Zika virus infection and possible diseases of the nervous system or defense system. For example, after the outbreak on the islands of French Polynesia, the incidence of Guillain-Barré syndrome increased twentyfold.
Zika virus infection in pregnant women
A Zika virus infection usually heals after a few days without consequences. Only the skin rash remains for about a week. If the Zika virus affects pregnant women, the pathogen can be transferred to the child via the blood.
There is no risk for the unborn child, if a women gets pregnant afrer a healed Zika Virus. According to todays knowledge, the Zika virus disappears completely from the body.
In this case, the development of the child can be severely disrupted. Then, there is a microcephaly. The children are born with a small (micro) head (-cephalus). The brain is often damaged and the affected child mentally handicapped.
Guillain-Barré syndrome after Zika virus infection
Also for adult infected people, a Zika virus infection can have dangerous consequences. In individual cases, the infection causes a Guillain-Barré syndrome. This is a rare neurological disease, which manifests symptoms of paralysis, which can also affect the respiratory muscles in the worst case. About 20 percent of patients remain physically disabled, about five percent die.
Zika virus causes and risk factors
In the case of a Zika virus infection, two important factors must be taken into account:
On the one hand the occurrence of the Zikavirus itself, on the other hand its transmission by Aedes mosquitoes on humans.
The Zika virus belongs to the family of the Flaviviridae and the genus of the flaviviruses. This group also includes, for example, the virus of tick-borne early summer meningoencephalitis.
Well-known other flaviviruses are the dengue, the West Nile and the yellow fever virus. In a Zika virus infection, the single-stranded RNA virus affects body cells. However, how it penetrates exactly into the human cells and which sequences follow is still being investigated. In general, invaded viruses use human cell components to multiply.
Transmission of the Zika virus
According to the present knowledge, the Zika virus is transferred only by mosquitoes of the Aedes genus from person to person. Well-known representatives are Aedes albopictus and Aedes aegypti, which can also transmit the yellow fever, Chikungunya and Dengue virus.
The Zika virus multiplies after the stab in the human body. In new stitches, the mosquito takes up the pathogen again, transfers it to other persons and thus spreads a Zika virus infection. People and primates are the main carriers of the Zika virus.
Among the dangerous mosquitoes is the Aedes albopictus. It is about five millimeters small, black-silver-white striped and found on almost the whole world, which is why experts do not rule out the spread of the Zika virus to other countries, including Europe.
Zika virus infection during sex
The Zika virus can also be transmitted during sex – even if the transporter no longer feels any symptoms. Especially men are carriers, presumably because the viruses manage to hide in the shielded area of the testicles longer in front of the immune cells. Therefore, male travelers from Zika regions should have to use condoms for at least eight weeks after their return home. On the other hand, women transmit the virus only in the acute stage of the disease.
Zika virus infection over blood
The Zika virus can also be found in blood transfusions in theory. However, a transfer in this way is considered extremely unlikely and has only been proven in a few cases. Nevertheless, travel agents from affected regions are not allowed to donate blood for a few weeks.
Zika virus diagnosis and investigation
If you suspect that you have a Zika virus, there is no reason to worry. The disease is usually mild and disappears after a few days. If you have returned from a holiday or have been in contact with potentially infected persons, you should consult your GP or a specialist in tropical medicine.
The zika virus symptoms also occur in other travel disorders which can lead to a much more severe course. Pregnant women are also advised to have a doctor’s visit because a Zika virus infection can cause damage in the child’s development (especially at the beginning of pregnancy).
The collection of medical history is of crucial importance. The doctor first asks about possible Zika virus symptoms. Most important are information about recent travel. The doctor may ask the following questions:
- Since when do you have complaints?
- When was the last time you were abroad?
- Where are you hanging out and how long have you been there?
- Have you been bitten by mosquitoes?
- Have you recently measured elevated body temperatures?
- Have your complaints subsided in the meantime and are now increasing again?
- Do you have joint pain, red eyes or skin rashes?
After the detailed survey, your doctor will physically examine for a Zika virus infection. Your doctor will measure your body temperature, scan lymph nodes and examine the skin for possible rashes. Doctor will also pay attention to your joints and rule out other possible causes of joint pain. Red eyes give the doctor a decisive indication of conjunctivitis.
To diagnose a Zika virus infection, the doctor must take several blood samples. Some values may deviate from the normal value and generally indicate an infectious disease. For example, the number of white (leukocytes) and red (erythrocyte) blood corpuscles as well as the amount of platelets (platelets) are determined. Especially the blood platelets are typical for Chikungunya and even more for Dengue fever.
The genome of the Zika virus is detected for reliable detection. This is done by means of a special laboratory procedure called “reverse transcriptase polymerase chain reaction” (RT-PCR). The Zika virus RNA is thereby multiplied and can be determined in this way. In this way, the Zika virus infection can be secured within the first days after the onset of symptoms. In addition, laboratory workers can examine infected blood for specific antibodies to the Zika virus.
However, these laboratory procedures sometimes show incorrect results because the substances used react with other flaviviruses (cross-reactivity). In the so-called neutralization test, however, a reliable detection of the Zika virus infection succeeds. However, this method takes several days and is very complex, which is why the faster and more cost-effective RT-PCR is the standard procedure.
Up to two weeks after the first symptoms, Zika virus can be recovered from the urine of affected person.
Dengue fever, chikungunya and other diseases
When examining a Zika virus infection, the doctor tries to exclude other tropical / travel diseases. This is especially important, since Zika virus infection is mostly harmless, but other diseases can be much more complex with symptoms that are similar in the beginning.
The focus is on dengue and chikungunya. However, leptospirosis, malaria, rickettsia or alphaviruses, rubella, and enterovirus or parvovirus infections are also possible causes of the symptoms.
In addition, the white blood cells in chikungunya are usually significantly lower than in a Zika virus infection or dengue. On the other hand, the platelets fall into a critical area especially during dengue fever. At chikungunya, their number is only slightly decreased.
Zika Virus Treatment
There is no therapy that works directly against the Zika virus. Therefore, the Zika virus treatment is limited to alleviating symptoms of the disease. We recommend bed rest and sufficient fluid intake, as the body can lose a lot of water during the disease phase.
Medications alleviate Zika virus symptoms such as pain (analgesics) and fever (antipyretics). For the Zika virus treatment, doctors recommend acetaminophen (paracetamol) in particular to reduce the risk of bleeding.
Acetylsalicylic acid which interferes with the function of blood platelets, should be dispensed with. If you are taking acetylsalicylic acid due to other conditions, consult your doctor for advice. In the case of further disease symptoms of a Zika virus infection such as a conjunctivitis, the treatment is extended correspondingly.
Zika Virus Prevention
The Zika virus can neither be treated nor is vaccination available so far. In risk areas, it is important to protect yourself against risky mosquitoes. Even those who are already infected should avoid further mosquito bites in the first week so that they are not infected with these people.
The following measures protect you before stings:
- Use insect repellents
- Wear long trousers and long-sleeved clothes. For additional protection against mosquito bites and against a Zika virus infection, you can spray your clothes with permethrin
- Pay attention to mosquito nets, especially over the bed and windows. This is especially during the day as the Zika virus mosquitoes are particularly aggressive at this time. Again, you can protect yourself against Zika virus infection by spraying the mosquito net with permethrin. Keep in mind that high levels of sunshine can cancel the permethrin protection
- Avoid and eliminate water bodies. Empty water and waste bins regularly or cover places where new mosquitoes can ripen. Avoid residing in the direct vicinity of pools or similar water bodies. It may be necessary to use insecticides
- Do not travel in risk areas if you are health-restricted or pregnant. Keep to the current recommendations of the health authorities. For further information on the current state of Zika virus infections, see the World Health Organization.
- Tell your doctor if you are going on a trip. This applies in particular to pregnant women who return from a risk area. Report your vet from your trip at the latest check-up. In the case of a disease, you will be tested for a Zika virus infection and, if necessary, initiate further examinations. If you feel healthy, your doctor will use the information to monitor ultrasound especially early signs of a flawed brain and skull development of the child
- Not only in a Zika virus infection, but also in general: Find a doctor immediately if you suffer from symptoms such as fever, reddened eyes, rash, nausea, headache and limb pain, especially on or after travelling to risk areas
- Do not hesitate to visit clinics in your country. In this way, other more severe diseases can be detected and treated at an early stage. Also protect yourself from mosquitoes during this time so that the spread of a Zika virus infection can be absorbed
Zika virus vaccination
A medication for a Zika virus infection is not yet possible. However, the first promising studies have already started.
Zika Virus Disease History and Prognosis
The Zika virus infection often occurs without any signs of a disease. Therefore, many infected people do not even notice that they carry the virus within themselves. If symptoms occur, the symptoms last only a few days to a week. The skin rash is usually the longest. Treatment in the hospital is only necessary in exceptional cases.
Zika virus complications
The most dangerous complication of a Zika virus infection affects unborn children. If the mother is infected, there is a risk of microcephaly. The heads of the affected children are abnormally small, and their brain is also deformed, resulting in serious mental disabilities or even the early death of the child. This can also be the case if the mother had not noticed any symptoms of the disease.
Guillain-Barre Syndrome: For adults, the risk of Guillain-Barré syndrome increases after a Zika virus infection. This is a neurological disease in which the nerves are ignited due to misdirected immune reactions. This results in paralysis symptoms and sensory disturbances, which usually begin at the legs and rise to the trunk. In the worst case, this can lead to paralysis of the air and thus to death.