How the Wuhan coronavirus compares to the world’s biggest killer diseases

South Africa is on high alert for any sign of the new Wuhan virus that has emerged from China, joining many other countries.

The South African Health Department said that the virus – called the Novel Coronoavirus or 2019-nCov – has not appeared up in South Africa, adding that measures are in place to screen travellers from source countries.

“Due to the current risk of importation of inadvertent cases of 2019-nCoV from Wuhan City, China, Port Health authorities have enhanced surveillance of all travellers from Asia, especially China.

“Fortunately, OR Tambo International Airport is the only port of entry for all flights from Asia,” the ministry said.

As it currently stands, the virus is mainly affecting China and a few of its provinces, with a fatality rate of 3.1% – being 26 deaths from 830 cases on record.

The World Health Organisation’s Emergency Committee has met over the outbreak, and has determined that it does not constitute an international emergency at this stage.

“As this is a new coronavirus, and it has been previously shown that similar coronaviruses required substantial efforts for regular information sharing and research, the global community should continue to demonstrate solidarity and cooperation in supporting each other on the identification of the source of this new virus, its full potential for human-to-human transmission, preparedness for potential importation of cases, and research for developing necessary treatment,” the WHO said.

The virus is similar to other coronaviruses which have emerged over the last 20 years, such as the Severe Actute Respiratory Syndrome-related virus (SARS) and the Middle East Respiratory Syndrom virus (MERS), which broke out in 2002 and 2012, respectively.

While these outbreaks have led to relatively fewer deaths than some of the world’s biggest killer diseases, they are part of the bigger picture – particularly when their end-point is pneumonia, which is still the communicable disease which kills the most people each year.

This is how the Novel Coronavirus fits into the global prevalence of disease:

Coronavirus – around 400 a year (during outbreaks)

The coronoavirus is spread largely between mammals and birds – and in humans causes complications with the respiratory system.

The most notable coronavirus outbreaks are the 2002/03 SARS and the 2012/13 MERS outbreaks, which together claimed 1,600 lives over the four years.

While the Wuhan virus has been identified as a coronavirus, the World Health Organisation does not yet have enough data to determine the severity of the outbreak relative to these two cases.

In the case of both the SARS and MERS outbreaks, symptoms were flu-like, progressing to pneumonia and severe respiratory problems. Fever, coughing and shortness of breath are key indicators.

Dengue Fever – 1,000+ a year

Dengue fever is a growing worry at the World Health Organisation, with half the world’s population at risk.

Like Malaria and Zika, the Dengue virus is mosquito-borne, and thus can spread quickly among populations. It is estimated that there are 390 million new infections each year.

While the virus seldom leads to death – with around 1,000 recorded each year – if not managed, it places sufferers at risk, with children particularly vulnerable.

Symptoms of the virus are flu-like, including severe headaches, nausea, fever and swelling. The virus is severe when blood starts factoring in, with bleeding gums, or patients vomit blood.

There is no specific treatment for the virus.

Cholera – up to 143,000 a year

Researchers have estimated that each year there are 1.3 million to 4.0 million cases of cholera, and between 21,000 and 143,000 deaths worldwide.

It is an easily treatable disease, however outbreaks typically occur when conditions are severe (after floods, earthquakes, etc), making it difficult to treat those who need it.

The WHO is seeking to reduce cholera cases by 90% by 2030, using hygiene and aid campaigns.

Cholera pandemics have struck since the 1800s, and to this day the disease continues to affect millions of people, resulting in tens of thousands of deaths each year.

Big cholera pandemics in regions such as China, Russia and India have lead to the deaths of almost 40 million people. One of the largest outbreaks hit India in the early 20th century, killing over 800,000 people in just over two decades.

Typhoid – 160,000+ a year

When people advise you against eating raw meat or eggs over fear of “salmonella”, this is what they want you to avoid.

Typhoid, or Typhoid fever is caused by the Salmonella bacteria which can be prevalent in animals and spread to humans through uncooked or unprepared foods or contaminated water. The disease spreads by Salmonella invading the bloodstream and then spreading to the organs.

Typhoid fever can be treated with antibiotics although the World Health Organisation has warned that increasing resistance to different types of antibiotics is making treatment more complicated.

The WHO estimates that over 160,000 people die from the disease every year, with other estimations as high as 220,000 people.

Malaria – 430,000+ a year

How many people have died from Malaria in history? The truth is, we don’t really know – but we do know that it’s a lot (in the billions), and the disease continues to be one of the biggest killers even today.

According to the latest data from the World Health Organisation (2018), annual malaria deaths are declining, but the disease remains one of the most prolific illnesses across the globe with as many as 220 million infections in 2017 alone.

In 2017, there were an estimated 435,000 deaths from malaria globally, compared with 451,000 estimated deaths in 2016, and 607,000 in 2010, the WHO said in its latest report.

Historically, in 1999, the WHO reported that malaria could have claimed the lives of close to 200 million people in the 19th century alone. In the late 90s and early 2000s, approximately 1 million people a year lost their lives to malaria.

Researchers have pointed to malaria being with humanity for over 500,000 years, with startling claims that the disease has wiped out half the people who ever walked the earth. With some estimates that over 100 billion have lived on earth, at face value this means malaria could have killed 50 billion people.

Speculative historical figures aside, malaria remains one of the biggest killer disease in the world today.

Influenza – up to 650,000 year

The flu is one of the biggest killers in the world, with the WHO estimating between 290,000 and 650,000 deaths each year. These estimates could be considered conservative, as it only accounts for respiratory-related deaths tied to the flu.

The flu has been with humanity a long time, and has caused millions of deaths over the last century.

The WHO estimates the total death toll from the 1918 flu pandemic at around 50 million casualties – however other experts on the matter believe the global impact could be as high as 100 million people.

Before and since the 1918 crisis, there have been a number of flu outbreaks, including viral strains from animals such as birds and pigs, which have also claimed millions of lives.

Record of various global flu outbreaks between as early as 1760 and up to 2009 put additional deaths due to flu close to 50 million people.

AIDS – 770,000+ a year

HIV/AIDS was first recognised at a disease in the early 1980s, and has since grown into a global pandemic affecting millions across the globe.

According to data compiled by UNAIDS, approximately 32 million people have died due to AIDS-related illnesses since 2001, with the total deaths since its discovery pegged at around 36 million people.

It’s estimated that, globally, 37.9 million people were living with HIV at the end of 2018, with annual mortality at 770,000.

Tuberculosis – 1.5 million+ a year

Tuberculosis, along with HIV/AIDS holds the title as the leading cause of adult mortality in the world today, killing between 1.5 million annually.

The WHO estimates that approximately 2 billion people are infected, with less than half of all TB cases ever diagnosed.

Research suggests that as many as 1 billion people have lost their lives to TB over the past two centuries – and projections by the WHO to 2020 have a best- and worst-case scenario pointing to 60 million – 90 million deaths, respectively.

The good news is that TB incidence is falling at about 2% per year, however, the WHO says this needs to accelerate to a 4–5% annual decline to reach the 2020 milestones of the End TB Strategy.

Pneumonia – 2.2 million+ a year

Pneumonia is the end point for a lot of severe respiratory illnesses, and can be caused by viral, bacterial and even fungal infections. It is the leading cause of death among children under 5 around the world, and along with other lower respiratory infections, is the biggest killer among communicable diseases.

The lungs are made up of small sacs called alveoli, which fill with air when a healthy person breathes. When someone has pneumonia, the alveoli are filled with pus and fluid, which makes breathing painful and limits oxygen intake.

According to Institute for Health Metrics and Evaluation, while the number of death attributable to pneumonia is declining every year, it still leads to the deaths of over 2.2 million annually.

Pneumonia is preventable, but requires proper nutrition and healthcare, which is typically not prevalent in the regions where most people fall ill.

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