The current population of India is 1,328,895,718 as of Saturday, August 20, 2016, based on the latest United Nations estimates, accounting for nearly 18 percent of the world’s population and placing them second only to China for the most people.

However, a UN Report published last year says that India’s will likely surpass China in 2022.

Despite being one of the world’s largest economies, the country has some serious issues with poverty and some of the most severe issues with infectious diseases on the planet and here I’d like to look at that.


Soil-transmitted helminths

The World Health Organization (WHO) says soil-transmitted helminth (STH) infections are among the most common infections worldwide and affect the poorest and most deprived communities. They are transmitted by eggs present in human feces which in turn contaminate soil in areas where sanitation is poor.

In India, the number of cases of the top three STH, Ascaris lumbricoides, Trichuris trichiura and the hookworms totals more than 280 million cases.

Morbidity is related to the number of worms harbored. People with light infections usually have no symptoms. Heavier infections can cause a range of symptoms including intestinal manifestations (diarrhea and abdominal pain), general malaise and weakness, and impaired cognitive and physical development. Hookworms cause chronic intestinal blood loss that can result in anemia.

Visceral leishmaniasis

Visceral leishmaniasis, also known as kala-azar, is caused by the vector borne parasite, Leishmania donovani and can cause very serious systemic disease. Doctors without Borders (MSF) says Kala-azar is the second largest parasitic killer in the world, only behind malaria.

It is estimated that of the between 200,000 and 400,000 new cases a year, India accounts for approximately 60 percent of cases, with a bulk of the cases in the East India state of Bihar.

Dengue fever

Dengue fever is an infectious disease carried by mosquitoes and caused by any of four related dengue viruses. This disease used to be called “break-bone fever” because it sometimes causes severe joint and muscle pain that feels like bones are breaking.

There are three types of dengue fever in order of less severe to most: the typical uncomplicated dengue fever, dengue hemorrhagic fever (DHS) and dengue shock syndrome (DSS).

A study in the American Journal of Tropical Medicine and Hygiene by Brandeis University researchers suggests India sees some 6 million dengue fever cases annually while other estimates dwarf that number at more than 30 million per year. Either way, it’s much higher than what the Ministry of Health reports each year.


Some estimates say India accounts for 35 percent of the world’s malaria burden. Another paper estimates the malaria burden in India at India at 180 million, with as many as 90 million cases of P. falciparum malaria per year.

A study conducted by teams from the office of the Registrar General of India, Centre for Global Health Research at St Michael’s Hospital and University of Toronto, Canada, published in The Lancet on 20 November 2010 has reported that malaria causes 205,000 malaria deaths per year in India before age 70 years

No matter what numbers you use, malaria is a huge burden in India.

Elephantiasis  of leg due to filariasis/CDC
Elephantiasis of leg due to filariasis/CDC

Lymphatic Filariasis

The Global Network for Neglected Tropical Diseases says lymphatic filariasis (LF), also known as elephantiasis, infects an estimated 67 million people in 80 countries worldwide, and is an extremely painful, debilitating and disfiguring disease. Found mainly in tropical and sub-tropical climates, the disease is caused by the thread-like parasitic filarial worms Wuchereria bancrofti and Brugia malayi, which live in the lymphatic system and can cause extreme swelling of the extremities and genitals. More than 40 million sufferers of elephantiasis are seriously incapacitated and disfigured from the disease.

India reports about 6 million LF cases and the South Asia region 60 million.


India reports about one million cases of the blinding bacterial infection, trachoma. Trachoma is an infectious disease of the eye caused by the bacterium Chlamydia trachomatis, and is the world’s leading cause of preventable blindness. Approximately 41 million people in 57 countries worldwide have active trachoma, and an estimated eight million have lost their sight due to complications from the disease.


According to official reports received from 103 countries and territories, the global registered prevalence of leprosy at the end of the first quarter of 2014 stood at 180,464 cases. India has more than 87,000 registered cases, or more than four out of 10 cases globally.

WHO says leprosy is caused by a slow-growing bacillus, Mycobacterium leprae. It is transmitted via droplets from the nose and mouth of untreated patients with severe disease, but is not highly infectious. If left untreated, the disease can cause nerve damage, leading to muscle weakness and atrophy, and permanent disabilities.

Leprosy can be easily treated with a 6–12-month course of multidrug therapy. The treatment is highly effective, and has few side-effects and low relapse rates; there is no known drug resistance.

Close-up of a dog's face during late-stage "dumb" paralytic rabies/CDC
Close-up of a dog’s face during late-stage “dumb” paralytic rabies/CDC


According to the Global Alliance for Rabies Control, rabies is currently responsible for an estimated 59,000 human deaths a year, almost all transmitted via dog bites. Up to 60% of all rabies deaths are children under the age of 15.

Of the global total of human rabies deaths, India accounts for one-third, or 20,000 deaths.

Clearly, this list is not all-inclusive of the infectious disease issues in India, but you get the picture, there are many infectious disease problems in the world’s second most populous country.