You are more likely to catch colds during winter than in summer. Cold weather itself doesn’t cause colds, but it helps them spread. Many viruses, like the flu and COVID-19, thrive in cold, dry air. These conditions keep viruses infectious longer and help them multiply faster.
Cold weather also weakens the immune system, making it harder to fight infections. Still, viruses and bacteria—not the cold—are the real cause of illness.
Dengue fever is the world’s fastest-spreading mosquito-borne virus. Its range has extended drastically over the last six decades. Much of this transformation is the result of climate change.
Ebola is a virus that affects humans and causes high death rates. It is highly contagious and resists many current treatments.
Avian flu is a viral disease affecting wild birds and poultry. Though rare, it can spread to humans and other animals.
The World Health Organization (WHO) estimates 247 million people contracted malaria in 2021. 618,000 died, the majority of them children younger than five years old. The extreme toll wrought by malaria highlights the need for improved treatment methods.
Mosquitoes spread deadly diseases worldwide, including dengue fever, Zika virus, and chikungunya. The tiny insects are responsible for millions of deaths each year.
Malaria, though preventable, remains one of the world’s deadliest diseases. Nearly half a million African children under five die from malaria every year. In 2021, over 100 million people contracted malaria, and hundreds of thousands succumbed.
The summer flu is a viral respiratory infection, similar to the flu. While the flu virus is most active from fall to winter, it can spread year-round. Summer flu-like symptoms may stem from other illnesses.
Cholera is a serious infectious disease affecting many countries worldwide. It causes severe diarrhea and incurs high death rates. Children and pregnant women are at severe risk of fatality from the disease.
