Breakthrough infection

Breakthrough infection refers to the case where an individual contracts an infection despite being vaccinated against it. This phenomenon is not uncommon and is expected in any vaccination process, as no vaccine provides 100% protection. However, the severity of the infection in such cases is usually lower than in unvaccinated individuals.

Definition

A breakthrough infection is defined as the detection of SARS-CoV-2 RNA or antigen in a respiratory specimen collected from a person ≥14 days after they have completed all recommended doses of a COVID-19 vaccine.

Causes

Breakthrough infections can occur due to several reasons. The primary cause is the inherent inability of any vaccine to provide 100% protection. Other factors include the individual's immune response, the presence of variants of concern, and the time elapsed since vaccination.

Implications

While breakthrough infections can cause concern, it is important to note that they are expected and do not necessarily mean that the vaccine is ineffective. Vaccinated individuals with breakthrough infections are less likely to experience severe disease, hospitalization, or death compared to unvaccinated individuals.

Prevention

Preventing breakthrough infections primarily involves continuing to follow public health guidelines even after vaccination. This includes wearing masks, practicing social distancing, and maintaining good hand hygiene.

Research

Research is ongoing to understand the factors contributing to breakthrough infections and to develop strategies to minimize their occurrence. This includes studies on vaccine efficacy against different variants and the potential need for booster doses.

See also

• COVID-19 vaccine
• Vaccine efficacy
• Variants of concern
• Public health