Health Statistics

The data collected from either active or passive surveillance is a form of evidence that can inform evidence-based policymaking. For example, the local government can use data on the number of smokers in a town to justify starting a public anti-smoking campaign in the local area.

Epidemiology and Health Statistics

Epidemiologists will collect relevant health information to understand and analyse the frequency and the spread of disease, which will subsequently allow them to inform future strategies for health management.

Three indicators provide crucial information for this:

• Incidence – measures the number of new disease cases within a given time.

• Prevalence – measures the number of people with the disease in a population.

• Mortality – measures the number of people who have died from the disease.

Endemic vs Epidemic vs Pandemic

The spread and prevalence of a disease can be classified into three primary categories:

• Endemic disease
• Epidemic disease
• Pandemic disease

Endemic Diseases

An endemic disease is any disease outbreak that is constantly present but contained within a specific country or region.

For example, malaria is an infectious disease that is endemic to some African countries. It is a mosquito-borne parasitic infection transmitted (spread) by mosquitoes. If it isn’t treated within a reasonable time, it can be fatal. There have been great strides in increasing access to antimalarial medications and vaccinations in Africa over the last two decades, and incidences are gradually decreasing.

Epidemic Diseases

An epidemic is any disease outbreak that spreads rapidly within a population over a very short time. Epidemics are not just limited to infectious diseases; they can also refer to any disease that causes debilitating effects to a large population. For example, the rapid rise in obesity rates in Western countries, like the USA, is considered an epidemic. Obesity is a significant risk factor for various diseases, such as cancer, cardiovascular diseases and strokes.

Fig. 1 - A graph showing an increase in adult obesity rates in the United States from 1960-2015. You can see that by 2010 the obesity rate reached nearly 40% of the total population in the US

Pandemic Diseases

A pandemic is any disease outbreak that describes the rapid spread of an infectious disease to other countries, continents and potentially worldwide. When an epidemic affects other countries and continents, it is known as a pandemic.

An example of a pandemic is the coronavirus outbreak in late 2019. Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus initially detected and transmitted in China. The coronavirus spread quickly across Asia and soon to the rest of the world. The number of deaths worldwide reached more than 5 million in late 2021. These deaths were exacerbated by the fact that there were no effective vaccines against COVID-19 until late 2020 when the first vaccines were administered to the public. The vaccines have largely reduced the spread and severity of COVID-19.

Types of Health Statistics

The collection of health statistics data with regards to a specific condition or illness is often conducted by designated public health organisations. The information obtained from the data can then be interpreted at the level of the country or brought together globally so that the statistics collected by different countries can be compared to each other.

UK Health Statistics

The Office for Health Improvement and Disparities (OHID) is a newly formed sub-organisation of the Department of Health and Social Care (DHSC) within the UK government. This organisation publishes statistics on various health issues such as obesity, mortality, health inequality, and mental health.

Mental Health Statistics

According to the Office for National Statistics (ONS), the prevalence of moderate and severe depression among adults in Great Britain rose from 10% in March 2020 before the start of the pandemic to 21% by January to March 2021. This figure, however, had improved slightly by August 2021, when 17% of adults were reported to have had moderate or severe depressive symptoms.

With regards to children, a separate survey study found that the proportion of children aged between 6 and 16 with possible mental disorders had risen from 11.6% in 2017 to 17.4% in 2021. These figures show the psychosocial impact the COVID-19 pandemic has had on the mental health of adults and children in the UK.

World Health Statistics

The World Health Organisation (WHO) is an inter-governmental body that collects health statistics and data globally. Specific governments usually assess disease patterns in their country, while the WHO assesses disease patterns worldwide. Based on the data collected, the WHO can plan and implement strategies to combat health issues, such as providing free vaccinations to urgently requiring regions. Some health statistics examples include the number of people who have been reported to have a form of cardiovascular disease that has been collected.

Infectious Disease

Data collected by the WHO suggests that the major cause of death in developing countries is infectious diseases. In comparison, developed countries have much lower deaths from infectious diseases than developing countries. There are several reasons for this, including:

• Developing countries cannot afford basic medication to treat and cure infections, e.g., antibiotics to treat bacterial infections

• Developing countries have poor roll-outs of vaccines

• Poor standards of hygiene and nutrition due to poverty can increase infection spread in developing countries

• Lack of public health education in developing countries

Fig. 2 - A map of the world showing the prevalence of infectious and parasitic diseases. Dark red colour indicates the highest levels of infection, while light yellow indicates very low levels of infection. Africa and South Asia have very high levels of infectious disease, compared to other areas of the world

Cardiovascular Disease

Another health statistics example is the rate of deaths due to cardiovascular disease i.e., heart and circulation disease, per country. According to WHO, cardiovascular disease is the main cause of death in developed countries. Meanwhile, deaths in developing countries from cardiovascular disease are much lower.

The reason for this is due to lifestyle differences between developing and developed countries:

• People in developed countries generally consume diets that are higher in fat and salt

• The incidences of obesity are much higher in developed countries; obesity is a major risk factor for cardiovascular disease.

• The occurrence of tobacco smokers is much higher in developed countries; smoking is a major risk factor for cardiovascular disease.

• Many individuals in developing countries are subsistence farmers, meaning they grow crops for themselves. Therefore, a large portion of their diet consists of vegetables and fruits.