An epidemic refers to the rapid spread of an infectious disease in a given population within a short period of time. Several factors are responsible for triggering epidemics. Changes in the host population’s ecology such as an increase in the vector species density might cause an epidemic. Genetic mutations in a pathogen reservoir resulting in a novel or a newly emerging pathogen might lead to an epidemic. The host population usually lacks immunity to combat the infection by such a pathogen. When an epidemic spreads across many countries and even continents, it is termed a pandemic. Epidemics are of major global concern. If the spread of disease is not checked in time, it might wipe out entire populations in no time.
Although medical science has made great advancements in the current times, it does not mean that the world is guarded against any major epidemic from occurring in the 21st century. In fact, with growing populations, overcrowded urban areas increasing across the world, climate change, and globalization, the situation appears ideal for the occurrence of a major pandemic.
However, scientists and medical professionals are constantly working hard to develop vaccines and treatments for all major known pathogen strains so that an infectious disease outbreak can be nipped at the bud. Despite their efforts, several epidemics have occurred in this century and some have claimed the lives of hundreds to thousands of people. Here is a list of the deadliest epidemics of the 21st century to date.
2016 Yellow Fever Outbreak In Angola
On January 20, 2016, Angola’s health minister reported an outbreak of yellow fever in the country. 23 cases including 7 deaths were reported. The outbreak was initially reported on December 5, 2015. Visitors to Angola from Eritrea were the first to suffer from the disease during the outbreak. Soon, the epidemic spread among the Congolese and Eritrean citizens residing in the Viana municipality of Angola. Since the yellow fever outbreak took place in a city, chances of the disease spreading fast were high. Hundreds of deaths were reported in the next few months as the disease spread through the various provinces of the country. Soon, the epidemic crossed the boundary of Angola. 21 deaths from yellow fever were reported in the Democratic Republic of the Congo with some taking places in the provinces bordering Angola. A mass vaccination campaign was initiated to control the spread of the disease. Initial investigations revealed that the Eritrean visitors who were the first victims of this outbreak had carried fake yellow fever vaccination certificates to Angola. They all had a meal at the same restaurant from where they could have picked up the infection. Efforts at both national and international levels gradually brought the outbreak under control.
2013 West African Ebola Virus Epidemic
The world’s most widespread Ebola virus disease outbreak happened in West Africa in 2013 and lasted until 2016. Liberia, Sierra Leone, and Guinea were the worst affected countries. Major loss of life and socioeconomic losses were suffered during this epidemic. The first case was recorded in Guinea in 2013. The disease claimed hundreds of lives with a case fatality rate of more than 70%. After a peak in October 2014, things started getting under control as international efforts started bearing fruit. Finally, on March 29, 2016, WHO terminated the status of the epidemic as an emergency of international concern.
2009 Flu Pandemic
This pandemic is regarded as one of the deadliest disease outbreaks of this century to date. The H1N1 influenza virus was responsible for this outbreak. Although the precise origin of the disease is not known, it is estimated that the viral strain responsible for the pandemic first evolved in 2008. Initially, it circulated in the population for several months before being formally recognized. It was first recorded in the Mexican state of Veracruz. Despite attempts to contain it within the state, the epidemic soon became uncontrollable and spread to other parts of the country, the US, and even parts of Asia and Africa. Although reports mention that 18,000 people died due to the disease, the unofficial figures could be way higher.
2010 Haitian Cholera Outbreak
Although cholera outbreaks were very common in the past, modern sanitation systems have been able to contain the disease in most parts of the world. This beaten back disease, however, resurfaced in a never before imagined massive scale in Haiti in 2010. Although the source of the disease was not revealed, investigations by journalists revealed that the contamination resulted from infected Nepalese UN peacekeepers deployed in Haiti. By March 2017, the disease had claimed the lives of 9,985 Haitians and many others.
2002 SARS Outbreak
SARS or Severe Acute Respiratory Syndrome is a zoonotic disease caused by the SARS coronavirus. On November 2002, an outbreak of SARS was reported in China. It caused a big scare across the world. The disease soon spread to other countries. Between November 2002 and July 2003, 8,098 cases of infected individuals were reported. 774 deaths were registered in 37 countries. After thorough investigations, scientists were able to trace the origin of this disease to Horseshoe bats in China’s Yunnan province.
2011 Dengue Fever Outbreak In Pakistan
Dengue fever is one of the infectious diseases that commonly occur in South Asian nations like India and Pakistan. Mosquitos are vectors and the dengue virus is the infectious agent in this disease. One of the worst outbreaks of dengue occurred in Pakistan in 2011 when over 300 people died of dengue fever. More than 21,204 people were infected by November 2010. Lahore area in Pakistan’s Punjab was the worst-affected during this outbreak.
2009 West African Meningitis Outbreak
This epidemic of bacterial meningitis occurred in several countries of West Africa including Nigeria, Niger, Burkina Faso, and Mali. 13,516 individuals were infected by the disease and the death toll was 931. Nigeria was the worst hit by this epidemic. Mass vaccination programs were conducted to keep the disease in check. Nearly one-third of the emergency vaccine stockpile of the world for the infectious bacterial strain causing the disease was consumed during this outbreak.
2012 Yellow Fever Outbreak In Darfur, Sudan
In 2012, a yellow fever outbreak was reported in Sudan’s Darfur region. By January 2013, 847 suspected cases and 171 deaths had been reported in the region. A mass vaccination campaign was initiated to protect the susceptible population against the disease.
2016 Yemen Cholera Outbreak
A cholera outbreak began in Yemen in October 2016. It is also considered to be one of the deadliest epidemics of the 21st century to date. The war situation in Yemen is regarded to be one of the biggest factors responsible for the disease outbreak. The destruction of the infrastructure, health and sanitation systems in large parts of the country due to war led to the spread of the disease. As of July 2017, 269,608 cases of cholera were reported in the country including 1,614 recorded deaths.
2008 Zimbabwean Cholera Outbreak
In 2008, large parts of Zimbabwe experienced a cholera outbreak. It lasted from August 2008 to June 2009. A national emergency was declared in December 2008 by the government of the country. International aid was requested to meet the emergency. In January 2009, the epidemic was at its peak and nearly 8,500 cases were reported every week during this time. Neighboring countries were also affected by the disease. In the end, 4,369 deaths were reported.
2012 Middle East Respiratory Syndrome Coronavirus Outbreak
A newly evolved strain of betacoronavirus led to the outbreak of this disease in 2012. The first case of the disease was reported in Saudi Arabia in April 2012. Since then, sporadic cases and large outbreaks have been reported in 24 countries. More than 400 deaths due to this disease have also been reported.