Cases of seasonal influenza are on the rise in Kathmandu, of late.
According to Sukraraj Tropical and Infectious Disease Hospital, at least 25 cases of influenza A have been reported in the hospital since January this year.
“At least 30-35 patients with symptoms of influenza are visiting the hospital’s OPD,” said Dr Milan Bajracharya, consultant physician at the Sukraraj Hospital.
The visitors show symptoms like cough, runny or stuffy nose, sore throat, fever, headache, fatigue and bodyache. Hospital officials say the infected have A(H1N1) and A(H3N2) viruses in their systems.
A contagious viral infection, influenza attacks the respiratory system. Type A influenza poses a serious threat to public health. According to the World Health Organization (WHO), it can cause widespread outbreaks and disease.
“Some of the children visiting the hospital showed symptoms like vomiting and diarrhea,” said Dr Sher Bahadur Pun, chief, Clinical Research Unit, Sukraraj Hospital.
Health experts warn that a large population may get infected if precaution is not taken.
Seasons of influenza
Each year, Nepal sees two seasons of influenza virus—in January-March and in July-August.
Change in weather is a major cause behind rising influenza cases in the country, according to the experts. “Whenever there is a difference of about 15 degrees between minimum and maximum temperatures, the human body faces difficulty adapting to changing weather. The body can’t maintain immunity and people fall ill,” said Dr Baburam Marasini, public health expert and former director at the Epidemiology and Disease Control Division (EDCD).
People from any age group can contract influenza, though those with low immunity, elderly, pregnant women, organ transplanted patients and cancer patients are more prone.
“The virus is already in the community. Keep in mind that it infects people with low immunity the most,” said Dr Bajracharya.
To reduce the severity of infection on people who have undergone organ transplantation, the experts advise maintaining minimum contact with visitors.
Cases are on the rise, but most of them go unreported. “We have call centers, but they receive very little information about influenza cases,” said Dr Abhiyan Gautam, deputy health administrator at EDCD.
Influenza cases are rising this year also because people have stopped practicing health safety measures, according to Dr Marasini.
According to him, the cases of influenza were fewer when the country was reeling under the Covid-19 outbreak. “People were alert; they were following safety health protocols, which shielded them from influenza,” said Marasini “But as the risk of coronavirus decreased, they stopped following health protocols, causing a surge in the number of flu cases.”
The experts warn that crowded areas like schools and offices offer a perfect setting for spread of the virus.
Per the WHO, when an infected person coughs or sneezes, droplets containing viruses are dispersed into the air and can spread up to one meter, and infect persons in close proximity who breathe these droplets in. The virus can also spread through infected hands.
Infections may rise in coming days, the experts say. “Children born when coronavirus was first detected in the country (2020) may be prone to infection as it is the first time they are coming into contact with the virus,” said Dr Marasini.
The experts point out that a large number of people may already have been infected, but most of them don’t want to visit hospital.
As for those staying home, they caution the former to not take medicines without consulting a medical practitioner. “Most of the people take antibiotics. It is counterproductive,” added Dr Bajracharya.
Experts say that most of the infected recover within a week without requiring medical attention.
However, influenza can cause severe illness or death, particularly among high-risk groups, including the very young, the elderly, pregnant women, health workers and those with serious medical conditions, the UN health body explains.
People, suffering from influenza, are also susceptible to pneumonia. Complications from the influenza are categorized as severe acute respiratory illness (SARI). According to the EDCD, 216 cases of SARI were reported on the 37th epidemiological week, while 247 cases were reported on the 36th week. The epidemiological week begins from the second week of January each year.
“For a week, I have been suffering from sore throat, cough, fever and body aches. I took rest and drank plenty of fluids. As it didn’t help, I visited a doctor. I am under medication now,” said Puja Budathoki (30) of Baneshwor.
Medical experts suggest people to visit health centers if they have complications.
Earlier on 29 March 2019, a 21-year-old male had succumbed to influenza A (H5N1). That was the first reported human case of Influenza A in Nepal.
The EDCD has been providing medicines to patients suffering from SARI for free.
Oseltamivir, sold under the brand name Tamiflu, is an antiviral medication used to treat and prevent influenza A and influenza B, viruses that cause the flu.
The first outbreak of influenza in Nepal, caused by influenza A/H3 serotype, was detected in 2004 at a Bhutanese refugee camp in southeastern Nepal. Since then, the country has witnessed an increasing number of influenza positive cases with two major epidemics in 2004 and 2009. The epidemic in 2009 was due to influenza A (H1N1), with the first cases seen in June 2009 among people returning from the US.
Kathmandu at increased risk
A study conducted by Bimalesh Kumar Jha and his team in 2016-17 and published in 2020 in National Library of Medicine found the prevalence of influenza to be higher in Kathmandu and nearby districts.
Because the transmission of influenza virus mainly occurs through aerosol inhalation and spreads more rapidly in crowded areas, these districts had higher prevalence of influenza in comparison to other districts. The Kathmandu valley and nearby districts are surrounded by mountains and experience distinct climatic conditions and lower temperatures, compared to other districts. As higher temperatures enhance defense mechanisms and decrease replication of influenza virus, the valley having lower temperature favors influenza virus replication, which might also be the reason behind higher prevalence rate, the team suggested.
To help prevent influenza, one must practise the same health measures such as maintaining social distance, handwashing and wearing masks, covering one’s cough and sneezes as they were done to prevent Covid infection, the experts advise. To prevent transmission, people should cover their mouth and nose with a tissue when coughing, and wash their hands regularly.