Zika Virus vs Dengue: Why India Is Facing a Growing Male Sexual Health Concern

Zika virus is commonly associated with mosquito bites, but the infection has another important dimension that men and couples planning a pregnancy should not overlook.

Unlike dengue, Zika can also be transmitted through sexual contact. The virus has been detected in semen and may remain there after other symptoms of infection have disappeared. This means that the risk does not necessarily end when fever, rash or other symptoms subside.

Zika is primarily spread by infected Aedes mosquitoes, the same mosquito group responsible for transmitting dengue and chikungunya. Most Zika infections cause no symptoms or result in a mild illness, but the virus becomes particularly significant when pregnancy and reproductive health are involved.

How Is Zika Different From Dengue?

Zika and dengue share several similarities. Both are mainly transmitted through infected Aedes mosquitoes and can cause fever, headache, muscle or joint pain and other flu-like symptoms.

The key difference is that Zika can also spread through sexual contact. The World Health Organization (WHO) says the virus can be transmitted sexually and from a pregnant woman to her fetus. Zika has been detected in semen and other body fluids.

As a result, someone recovering from Zika may still need to take precautions against sexual transmission even after the initial illness has passed.

Can Men Transmit Zika Without Having Symptoms?

Yes. A significant number of Zika infections are asymptomatic, meaning people may not realise they have been infected.

Sexual transmission has also been documented from people who did not experience symptoms. Therefore, the absence of fever or rash does not necessarily rule out infection.

Travel to an area where Zika transmission occurs, exposure to mosquitoes and other relevant risk factors can be important when assessing possible infection.

Does Zika Cause Male Infertility?

The detection of Zika virus in semen has raised questions about its potential effects on the male reproductive system. However, the presence of the virus in semen does not mean that every infected man will develop infertility or permanent reproductive damage.

Research into the long-term effects of Zika on male reproductive health is still evolving. The more firmly established concern is the possibility of sexual transmission to a partner, particularly when pregnancy is involved.

For couples planning to conceive, preventing transmission is therefore an important part of managing the infection.

Why Is Pregnancy a Major Concern?

The greatest health concerns linked to Zika involve infection during pregnancy.

If a pregnant woman contracts Zika, the virus can cross the placenta and affect the developing fetus. Infection during pregnancy has been associated with congenital Zika syndrome, which can include microcephaly, neurological abnormalities and developmental problems.

Zika infection has also been linked to complications including fetal loss and preterm birth.

This is why preventing infection during pregnancy — including infection acquired through sexual transmission — remains a major public-health priority.

Can Condoms Reduce Zika Transmission?

Yes. Consistent condom use can reduce the risk of sexual transmission of Zika.

The virus can potentially be transmitted through vaginal and anal sex and may also be transmitted through oral sex. Depending on the circumstances, health authorities may recommend condoms or abstinence for a specified period after infection or potential exposure.

The appropriate precautionary period can vary depending on whether a person was diagnosed with Zika, experienced symptoms, travelled to an area with transmission or is planning a pregnancy. Couples should discuss individual circumstances with a healthcare professional.

What Are the Symptoms of Zika?

Many people infected with Zika have no symptoms. When symptoms do occur, they are generally mild and may include:

• Fever
• Skin rash
• Red or irritated eyes
• Joint pain
• Muscle pain
• Headache
• Weakness or general discomfort

Symptoms usually last for several days to around a week.

Because Zika symptoms can resemble those of other mosquito-borne infections, including dengue, clinical assessment and laboratory testing may be required in appropriate cases. Testing can include molecular methods such as RT-PCR or antibody testing, although interpretation of some antibody results can be complicated by cross-reactions with related viruses.

What Should Men Do If They Suspect Zika?

Men who develop symptoms following possible exposure to Zika, or who have recently travelled to an area where the virus is circulating, should consult a healthcare professional.

A person should not assume that the risk of sexual transmission has ended simply because the fever or other symptoms have disappeared. Current public-health guidance recommends that men take sexual precautions for a specified period after infection or relevant exposure, with the exact advice depending on the circumstances.

Men who have confirmed or suspected Zika and are planning to have a child should discuss pregnancy timing and appropriate precautions with their doctor.

Zika Is More Than a Mosquito-Borne Infection

Zika should not simply be viewed as another mosquito-borne fever. Although most infections are mild or asymptomatic, the virus has a distinct reproductive-health dimension because it can be transmitted sexually and can remain detectable in semen after infection.

The key concern is not that every man infected with Zika will develop infertility. Rather, the established concern is preventing sexual transmission, particularly when a partner is pregnant or a couple is trying to conceive.

So, instead of asking whether Zika is simply “worse” than dengue, it is more useful to understand how the two infections differ. While both can be spread by Aedes mosquitoes, Zika carries an additional sexual and pregnancy-related risk that makes awareness and prevention especially important for men and couples.