• Most people who contract the chikungunya virus experience symptoms, which typically appear 3–7 days after being bitten by an infected mosquito.
• The hallmark signs are fever and joint pain, though other issues such as headache, muscle aches, joint swelling, and rash may also occur.
• Certain groups are more vulnerable to severe illness, including newborns infected around birth, adults aged 65 and older, and individuals with underlying conditions like hypertension, diabetes, or heart disease.
• While most patients recover within a week, joint pain can be intense, sometimes disabling, and may linger for months.
• Fatal cases are uncommon.

Global presence: Chikungunya virus is found across Africa, Asia, Europe, the Americas, and islands in the Indian and Pacific Oceans.

Virus family: It belongs to the alphavirus group within the Togaviridae family. Related viruses that cause similar illnesses include the Mayaro virus and the Ross River virus.

Transmission Patterns:

• Infection occurs when mosquitoes bite an infected person and later feed on another individual.
• During the first few days of illness, infected people have high levels of virus in their blood (viremia), enabling mosquitoes to pick it up and spread it.
• Preventive measures include avoiding mosquito bites and receiving vaccination before travel, if recommended.

• Rarely, the virus can pass from a pregnant woman to her fetus, most often during the second trimester.
• If infection occurs near delivery, the baby may acquire the virus at birth (intrapartum transmission), which can sometimes lead to severe illness.
• Chikungunya virus has not been detected in breast milk, and no cases of transmission through breastfeeding have been reported.
• Women who are breastfeeding and either infected or living in areas where the virus circulates should consult their doctor.

• Seek medical care if you develop symptoms after visiting areas where chikungunya is present.
• Inform your healthcare provider about your travel history (locations and dates).
• Tests can be ordered to detect chikungunya or rule out similar viruses such as dengue and Zika.

• No specific antiviral medication exists for chikungunya.
• Supportive care includes rest, hydration, and over-the-counter pain relief.
• Acetaminophen (paracetamol) can help reduce fever and pain.
• Avoid aspirin and NSAIDs (e.g., ibuprofen) until dengue infection is excluded, to lower bleeding risk.
• Prevent mosquito bites during the first week of illness, as the virus circulates in the blood at this stage.
• Mosquitoes feeding on infected individuals can transmit the virus to others.

• Dengue Infection has mild or no symptoms and gets better in a few weeks.
• Rarely, it can progress to severe forms such as Dengue Haemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) and may also lead to death.
• If symptoms occur, they usually begin 4–10 days after infection and last for 2–7 days. Symptoms may include High fever (40°C/104°F), severe Headache, Retro-orbital pain, Myalgia and Arthralgia, Nausea, Vomiting, Swollen glands, and Rash.
• Individuals with secondary infection are at greater risk of severe dengue. The symptoms of severe dengue often come after the fever has gone away and may include severe abdominal pain, persistent vomiting, bleeding gums or nose, fatigue, restlessness, and blood in vomit or stool.

• The available tests include nucleic acid amplification tests (NAATs), enzyme-linked immunosorbent assays (ELISAs), and rapid diagnostic tests (RDTs).
• There is no specific treatment for dengue; pain can be managed with medication such as paracetamol (acetaminophen).
• Non-steroidal anti-inflammatory medicines such as ibuprofen and aspirin should be avoided as they can increase the risk of bleeding.

• Aedes mosquitoes are a vector of dengue fever.
• It is a small mosquito, black with white stripes, and is approximately 3-5 mm in size.
• Favorite breeding places include Desert coolers, Drums, Jars, Pots, Buckets, Flower vases, Plant saucers, Tanks, Cisterns, Bottles, Tins, Tyres, Roof gutters, Refrigerator drip pans, Cement blocks, Cemetery urns, Bamboo stumps, Coconut shells, Tree holes, and many more places where rainwater collects or is stored.

• Only one approved vaccine currently: Q-denga (TAK-003).
• Recommended by WHO for children aged 6–16 years in high-transmission areas.
• Two-dose schedule: second dose after 3 months.

• The clinical presentation of Zika is frequently subtle, with up to 80% of infected individuals remaining asymptomatic.
• When illness does occur, symptoms are generally mild and typically last for 2 to 7 days. It presents as a self-limiting febrile disease accompanied by rash, myalgia, arthralgia, and conjunctivitis.
• However, the virus is infamous for its neurological and teratogenic complications. In adults, infection has been linked to Guillain-Barré syndrome, a serious autoimmune neuropathy.
• Even more devastating are the fetal consequences when a woman is infected during pregnancy. The virus can target the developing fetus, leading to congenital Zika syndrome. This encompasses a tragic spectrum of alterations including stillbirth, microcephaly, limited joint movement, and visual impairments.

• Confirming a suspected Zika infection presents a substantial diagnostic challenge for clinicians.
• First, because Zika symptoms closely mirror other arboviral diseases like dengue, clinical presentation alone is not enough; laboratory confirmation is required. Second, because the viremic phase is remarkably brief, typically lasting only 3 to 5 days after symptom onset. That is why nucleic acid amplification tests (NAATs or RT-PCR) must be timed perfectly.
• Once the virus clears from the blood, clinicians must rely on serological testing to detect Zika-specific IgM or IgG antibodies. Unfortunately, these tests are plagued by extensive cross-reactivity with other endemic flaviviruses, most notably the dengue and West Nile viruses.
• Consequently, positive or equivocal serological results routinely require confirmation via a highly specific plaque reduction neutralization test (PRNT), a method that is time-consuming, labor-intensive, and largely restricted to reference laboratories.

• Zika is principally an arbovirus; it is mainly transmitted to humans through the bite of infected mosquitoes of the Aedes genus (specifically Aedes aegypti and Aedes albopictus).
• However, epidemiological tracing reveals that mosquito vectors are not the sole route of exposure. The virus exhibits a unique capacity for human-to-human transmission, which includes vertical transmission from mother to fetus, sexual transmission, and spread via blood transfusions or organ transplantation.
• Furthermore, researchers are actively investigating the persistence of infectious viral particles in breast milk, though the definitive risk of transmission through breastfeeding remains an area of ongoing study.

• Currently, there is no licensed vaccine or specific antiviral available to prevent or treat Zika virus infection.