Consider seasonal influenza, also known as the flu. In terms of deaths and hospitalizations, the winter flu seasons in the United States in 2020 and 2021 were among the mildest on record. Nonetheless, cases increased in February and continued to rise throughout the spring and summer as Covid restrictions were relaxed.

Last summer, there was an increase in cases of the respiratory syncytial virus, a cold-like virus that is common during the winter months, with cases increasing among children in Europe, the United States, and Japan. Then, in January of this year, an outbreak of adenovirus 41, which is usually responsible for gastrointestinal illness, was identified as the cause of mysterious and severe liver disease in young children.

In other news, Washington State is experiencing its worst tuberculosis outbreak in 20 years.

And now, a recent outbreak of monkeypox, a rare viral infection found primarily in Central and West Africa, has health officials baffled, with over 1,000 confirmed and suspected cases emerging in 29 non-endemic countries.

Viruses gone wild

The US Centers for Disease Control and Prevention said last week that at least two genetically distinct monkeypox variants are now circulating in the US, most likely as a result of two separate spillover infections from animals to humans.

Although it is unclear whether the smallpox-like virus has mutated, health experts have reported that it is behaving in unusual ways. Most notably, it appears to be spreading within the community rather than through travel from areas where it is commonly found. Symptoms are also appearing in new ways.

The Centers for Disease Control and Prevention is also concerned that lockdowns may have caused many children to miss childhood vaccinations, potentially increasing the risk of other vaccine-preventable illnesses like measles and pertussis.

However, in the aftermath of the pandemic, there is now greater awareness and surveillance of public health issues, making diagnoses of some outbreaks more common.