Winter Flu in Pakistan: Symptoms, Prevention and When to See a Doctor

Winter is coming to Pakistan, and with it comes flu season. In Karachi, the change of season is already showing up in hospital wards: doctors told Dawn on 26 October 2026 that daily flu patients at Jinnah Postgraduate Medical Centre had roughly doubled in just over a week, from 30 to 40 a day to 70 to 80, while at Dr Ruth Pfau Civil Hospital the number rose from 8 to 10 a day to 30 to 40. Most of those patients can be treated at home. But flu is not always a small illness, and knowing when it needs a doctor can make a real difference.

This guide explains, in plain English, what winter flu is, how to tell it apart from a common cold, who is most at risk, what actually helps prevent it, what to do if you catch it, and the warning signs that mean you should get medical help straight away.

At a glance

• Flu season in Pakistan runs roughly from November to April, according to the National Institutes of Health (NIH) in Islamabad, with the peak usually in December to February.
• Flu comes on suddenly. A cold creeps in over a day or two; flu can hit within hours.
• Most healthy people recover in about a week with rest and fluids.
• The flu vaccine is the best protection, according to the World Health Organization (WHO). It is recommended every year for pregnant women, children under five, people over 65, and people with long-term illnesses.
• See a doctor early if you are in a high-risk group, and get urgent help for trouble breathing, chest pain or confusion.

What is winter flu?

Flu, or influenza, is an infection of the nose, throat and lungs caused by influenza viruses, mainly types A and B. It spreads when an infected person coughs, sneezes or talks, sending tiny droplets into the air, and when you touch a surface with the virus on it and then touch your mouth, nose or eyes.

Flu is not the same as a common cold, even though both are respiratory infections and both are more common in winter. A cold is usually caused by different viruses and stays mild. Flu can be much harder on the body, and in some people it leads to pneumonia and other serious problems.

The WHO estimates that seasonal flu causes about one billion infections around the world every year, including 3 to 5 million cases of severe illness and up to 650,000 deaths from respiratory causes.

Flu in Pakistan: what the numbers say

Pakistan’s NIH tracks flu through its Integrated Disease Surveillance and Response system, which counts suspected cases of influenza-like illness — fever with a cough or sore throat — from clinics across the country. These are suspected cases, not laboratory-confirmed flu, because colds and other viruses can cause the same symptoms.

In its advisory of 15 December 2025, the NIH reported 340,856 suspected influenza-like illness cases across Pakistan between epidemiological weeks 44 and 49 of 2025, roughly November to early December, with 12 per cent of tested samples positive for H3N2, the influenza A strain that dominated that season. The advisory also noted a new genetic subclade of H3N2, called subclade K, emerging around the world.

More recently, the NIH’s weekly bulletin for week 38 of 2026 counted 44,336 suspected influenza-like illness cases across the country, up from 41,735 the week before. Punjab did not report that week, so the true national figure was higher.

As of 30 September 2026, the NIH had not yet issued a new influenza advisory for the 2026–27 season; the latest one on its website was still the December 2025 advisory. That is one more reason to take the usual precautions early rather than waiting for an announcement.

What are the symptoms of flu?

Flu symptoms usually begin about two days after you catch the virus:

• Sudden fever or feeling feverish, often with chills
• A cough, usually dry at first
• A sore throat
• A blocked or runny nose
• Muscle and joint pain, often severe
• A headache
• Severe tiredness or weakness

Some people, especially children, also get vomiting or diarrhoea. Most people feel worst for the first three or four days, then slowly improve over about a week.

Flu or a cold? How to tell the difference

The quickest clue is speed. A cold builds up gradually: a scratchy throat one day, a blocked nose the next, a mild cough after that. Flu arrives suddenly — you can feel fine in the morning and ill by the evening.

Fever is another useful clue. Fever is common with flu and often high. With a cold, fever is rare, and if it appears it is usually low. Body aches and heavy tiredness point to flu; a cold usually leaves you able to carry on, even if you feel uncomfortable. Sneezing and a stuffy nose are more typical of a cold than of flu.

The difference matters: a cold almost never needs a doctor. Flu sometimes does.

Why flu spreads more in winter

Flu viruses survive longer in cold, dry air, and cold air dries out the inside of the nose, which makes it harder for the nose to trap viruses. People also spend more time indoors in winter, in closed rooms with the windows shut, which makes it easier for the virus to pass from person to person.

In Pakistan, winter also brings other pressures. Schools are in session, offices are full, and many families share bedrooms, bathrooms and meals. None of this means flu is caused by cold weather itself — it is caused by the virus. Cold weather simply gives the virus better conditions to spread.

Who is most at risk?

Anyone can catch flu, and anyone can become seriously ill from it. But the WHO says some groups face a much higher risk of severe illness and complications:

• Pregnant women, at any stage of pregnancy
• Children under five years old, especially those under two
• People aged 65 and over
• People with long-term medical conditions, such as asthma, chronic lung disease, heart disease, diabetes, kidney disease or liver disease
• People with weakened immune systems, for example because of HIV, cancer treatment or medicines that suppress the immune system
• Health workers, who are exposed to the virus more often

For these groups, flu can lead to pneumonia, hospital admission, and in the worst cases death. That is why the WHO recommends annual flu vaccination for all of them, and why doctors advise them to seek help early rather than waiting.

How to prevent flu

There is no single step that guarantees you will not catch flu. But several simple habits together cut the risk a lot.

Get the flu vaccine. The WHO calls vaccination the best way to prevent flu. The vaccine is updated each year because flu viruses keep changing, so last year’s vaccine does not give full protection this year. The best time to get it is before the flu season peaks — in Pakistan, that means October or November — but getting it later in the season can still help. In Pakistan, the flu vaccine is mostly available at private hospitals and pharmacies, and it costs money. If you are in a high-risk group, ask your doctor whether the vaccine suits you.

Wash your hands often. Wash with soap and water, especially before eating and after being in a crowded place or on public transport. Hand sanitiser works when soap and water are not available.

Cover coughs and sneezes. Cough or sneeze into your elbow, not your hand, and throw used tissues away straight away.

Keep some distance from people who are ill, and stay home when you are ill. If someone in the house has flu, give them their own space if you can, and their own glass, towel and plate. Open a window for a while each day to let fresh air in, even in winter.

Keep warm and look after your general health. Dress warmly, eat regular meals, drink enough water and get enough sleep. No vitamin, supplement or home remedy has been proven to prevent flu, and none of them replaces the vaccine.

What to do if you catch flu

Most healthy people do not need a doctor for flu. They need rest, fluids and time. The NIH says flu is usually self-limiting, which means the body fights it off on its own. Treatment is mainly about easing the symptoms while that happens.

Rest. Stay at home. Do not go to work, school or a crowded gathering while you have a fever. The US Centers for Disease Control and Prevention (CDC) advises returning to normal activities only when symptoms are improving and you have been free of fever for at least 24 hours without fever-reducing medicine.

Drink fluids. Water, soup, and warm drinks such as green tea or yakhni (chicken broth) help. Avoid alcohol. If you cannot keep fluids down, see a doctor.

Treat the fever and aches. Fever-reducing medicine such as paracetamol can ease fever and body aches. Use it as the label says, and ask a pharmacist or doctor if you are unsure.

Do not take antibiotics on your own. Flu is caused by a virus, and antibiotics do not work against viruses. A doctor may prescribe them only if a bacterial infection develops on top of the flu, such as bacterial pneumonia.

Antivirals work best early. The NIH recommends the antiviral oseltamivir, sold as Tamiflu, for hospitalised patients with severe or worsening illness and for people in high-risk groups. The CDC says antiviral medicines work best when started within one to two days of symptoms beginning, although starting later can still help people who are very ill or at high risk. That is another reason for high-risk patients to seek advice quickly rather than waiting.

When to see a doctor

See a doctor promptly if you are pregnant, older, very young, or living with a long-term medical condition and you develop flu symptoms. See a doctor quickly if your symptoms do not settle, if your fever lasts more than three days, or if an existing condition such as asthma or diabetes gets worse.

Seek urgent medical care the same day if you notice any of these warning signs, listed by the CDC:

• Difficulty breathing or shortness of breath
• Chest pain or pressure that does not go away
• Confusion, constant dizziness, or being unable to stay awake
• Not passing urine, or in children, no urine for eight hours
• Severe or persistent vomiting, or being unable to keep fluids down
• A child who is unusually sleepy, irritable, or not eating or drinking

In children, also watch for fast or troubled breathing. Babies under three months with a fever should be seen by a doctor the same day.

If you are not sure whether you need a doctor, it is better to call one and ask than to wait.

Flu in children, older people and pregnant women

Children under five catch flu easily and can become ill quickly, because their immune systems are still developing. Keep them home from school while they have a fever, give them plenty of fluids, and watch their breathing and drinking closely.

Older people may not always develop a high fever with flu, so a new cough, confusion, unusual tiredness or a sudden worsening of an existing condition can be the first sign. Because their risk of pneumonia and hospital admission is higher, doctors advise them to seek help early.

Pregnant women are at higher risk of severe flu, and the WHO lists them as the top priority group for vaccination. Pregnant women who develop flu symptoms should contact a doctor promptly rather than treating it at home alone.

Common myths about flu

“Cold weather gives you flu.” No. Flu is caused by a virus. Cold weather helps the virus spread, but you cannot catch flu just from being cold.

“The flu vaccine gives you flu.” No. Injectable flu vaccines are made from inactivated virus and cannot cause flu infection. A sore arm or mild tiredness for a day after the vaccine is the immune system responding, not the flu.

“I had flu last year, so I am immune.” No. Flu viruses change every year, and protection from a previous infection or vaccine fades over time. That is why the vaccine is recommended every year.

“Antibiotics cure flu.” No. Antibiotics treat bacterial infections, not viruses. They are only useful if a doctor finds a bacterial complication.

“Flu is just a bad cold.” For most healthy people, flu feels like a very bad cold that lasts about a week. But for people in high-risk groups, it can cause pneumonia, hospital admission and death — the WHO estimates up to 650,000 respiratory deaths a year.

Frequently asked questions

How long does flu last?

Most people recover within about a week, although tiredness and a dry cough can last two weeks or more. If you are still getting worse after a week, see a doctor.

When is flu season in Pakistan?

The NIH says Pakistan’s flu season runs from about November to April, with the peak usually between December and February.

Can I get the flu vaccine in Pakistan?

Yes. It is mostly available at private hospitals and pharmacies, and it costs money. Ask your doctor whether it suits you. The best time is before the winter peak, but it can still help later in the season.

Is it safe to take medicine for flu while pregnant?

Do not take any medicine without asking a doctor first if you are pregnant. Pregnant women with flu symptoms should contact a doctor promptly, because they are in the highest risk group.

Should my child stay home from school with flu?

Yes, while they have a fever. The CDC advises returning to normal activities only once symptoms are improving and the child has been free of fever for at least 24 hours without fever-reducing medicine. Keeping a sick child home also protects their classmates.

Conclusion

Winter flu is a normal part of the season in Pakistan, and for most people it passes in about a week with rest and fluids. But it is not a small illness for everyone. The Karachi hospitals reporting a doubling of flu patients in late October 2026 are an early sign that the season is starting.

The steps that work are simple and well proven: get the flu vaccine before the peak if you are in a high-risk group, wash your hands, cover coughs and sneezes, let fresh air into closed rooms, and stay home while you have a fever. If you do catch flu, rest, drink fluids, and watch for the warning signs. And if you are pregnant, very young, older, or living with a long-term condition, do not wait it out — seek medical advice early, because the treatments that help most work best when they are started quickly.

Sources

• World Health Organization, “Influenza (seasonal)” fact sheet — https://www.who.int/en/news-room/fact-sheets/detail/influenza-%28seasonal%29
• World Health Organization, “How can I avoid getting the flu?” — http://who.int/news-room/q-a-detail/how-can-i-avoid-getting-the-flu
• National Institutes of Health, Islamabad, advisory on prevention and control of seasonal influenza (H3N2), No. F.1-22/Advisory/CDC/2025, 15 December 2025, as reported by Kashmir English — https://kashmirenglish.pk/nih-issues-advisory-as-country-reports-over-300000-influenza-like-cases/
• NIH Integrated Disease Surveillance and Response weekly bulletins, weeks 37 and 38 of 2026, as reported by Pakera — https://pakera.pk/pakistan-flu-like-illness-pneumonia-cases-week-38-2026/ and https://pakera.pk/flu-vaccine-pakistan-2026/
• Dawn, 26 October 2026, on flu cases doubling at JPMC and Civil Hospital Karachi, as reported by Digital Akhbaar — https://digitalakhbaar.uk/hacks/flu-cases-karachi-symptoms-home-care-tips/
• US Centers for Disease Control and Prevention, flu guidance on antiviral timing, fever-free return and emergency warning signs, as quoted in the sources above
• Journal of Medical Virology, 2026, “Molecular Surveillance and Genomic Characterization of Influenza A(H3N2) Viruses From a Secondary-Care Surveillance Site in Pakistan During the 2025-2026 Winter Season” — https://pubmed.ncbi.nlm.nih.gov/42485504/

This article is for general educational purposes only. It is not medical advice and does not replace professional medical advice, diagnosis or treatment. If you are ill or worried about your health, speak to a qualified doctor.