Streptococcus pneumoniae (known as “pneumococcus“) is a bacteria that causes diseases such as middle ear infections, pneumonia, meningitis and septicaemia. It can cause fatal disease if not treated early enough with effective antibiotics. WHO estimate that around half a million lives are lost due to this bacteria each year. It is the leading cause of pneumonia deaths worldwide, mostly in children under the age of 5yo. Pneumococcus lives in the nose and throat of most of us at times, usually causing no symptoms or disease, but transmitting between us. In some studies up to 76% of children test positive to the bacteria without symptoms; the rate is lower in adults, but between 5% to 20%. It transmits by droplets and direct contact with infected secretions.
This is one example of many micro-organisms that transmit in this way. It is how respiratory-transmitted organisms survive and move amongst their human hosts and why the secretions from our noses and throats are considered unhygienic even when we are well. Ongoing and cyclical transmission of organisms amongst humans both assists our bodies in developing immunity and also leads to some people becoming sick. It is a silent battle our bodies are constantly fighting without us usually knowing it.
Whilst pneumococcus causes half a million deaths per year, it is not a pandemic but rather considered endemic; that is, an organism that we know is amongst us, not hurting most of us, yet causing significant harm to many who are vulnerable, but in numbers that we expect and accept. We have mitigations in place, including vaccines (inaccessible to the most vulnerable populations) and treatment (penicillin can kill it although there are strains which are resistant to penicillin and require other more expensive and difficult to access antibiotics). Hygiene is an important prevention measure as with most infectious diseases.
Today in many parts of the world, it seems that SARS-CoV-2, which causes Covid-19, is becoming an endemic organism. The pandemic in many countries is over. The graphs below illustrate why. Sadly, due to public perceptions / media hype / political face saving, this seems a very controversial thing to say. Yet the evidence speaks for itself. Obviously the pandemic is not over while places remain vulnerable to high rates of unexpected death. But there are places in the world (specifically most of Europe) who are much safer now that the virus has moved into an endemic phase. This is despite a rise in “cases” (which is largely asymptomatic carriage as people are encouraged to get tested) and despite ongoing low rates of death which are not impacting the overall death rate, nor impacting health services.
In fact, it seems that the definition of a “case” of Covid-19 may need to be reconsidered, as asymptomatic carriage seems an imprecise way to gauge whether someone is actually unwell or infectious. This is discussed in detail by Centre for Evidence Based Medicine in “When is Covid, Covid?“.
In these graphs the blue bars above the line are cases; red bars below the line are deaths.