We are in the era, where the world is facing multiple health challenges ranging from outbreaks of vaccinepreventable diseases, increasing number of drug-resistant pathogens, growing rates of non-communicable diseases, increasing rate of environmental pollution and climate change and multiple humanitarian crises. In this context, the World Health Organization (WHO) has listed out the top 10 global health threats19 which demand urgent attention from world health associations and WHO partners in 2019:

Air pollution and climate change

Nine out of ten people breathe polluted air every day killing 7 million people prematurely every year around the world. Around 90% of these deaths are in low- and middle-income countries, which have high volumes of emissions from industry, transport and agriculture, as well as dirty cookstoves and fuels in homes. Air pollution is a major risk factor for heart disease, stroke, chronic obstructive pulmonary disease (umbrella term for several progressive lung diseases including emphysema) and lung cancer, and increases the risks for acute respiratory infections and exacerbates asthma.

WHO recommends that the countries with air pollution need to strengthen their climate action plan. However, thet sources of air pollution being so diverse, only a combination of three systematic solutions would create maximum impact: 1) Replacing existing cooking stoves with clean cooking stoves; 2) Reducing pollution from diesel transport; and 3) Restricting open burning of biomass and fossil fuels.

Noncommunicable diseases (NCD)

Noncommunicable diseases, such as diabetes, cancer and heart disease, are collectively responsible for over 70% of all deaths worldwide, or 41 million people. 80% of NCDs deaths occur in low- and middle-income countries. This includes 15 million people dying prematurely, aged between 30 and 69. Over 85% of these premature deaths are in low- and middle-income countries. The rise of these diseases has been driven by five major risk factors - tobacco use, physical inactivity, the harmful effects of alcohol, unhealthy diets and air pollution.

Noncommunicable diseases are preventable through effective interventions that tackle these shared risk factors. If the major risk factors for noncommunicable diseases were eliminated, around three-quarters of heart disease, stroke and type 2 diabetes would be prevented; and 40% of cancer would be prevented.

Global influenza pandemic

There are three types of influenza; seasonal, pandemic and zoonotic. A pandemic occurs when an influenza virus which was not previously circulating among humans and to which most people don't have immunity emerges and transmits among humans. These viruses may emerge, circulate and cause large outbreaks outside of the normal influenza season. The most notorious pandemic for which data is available was the "Spanish Flu" in 1918- 1919 which caused an estimated 20-50 million deaths worldwide. The WHO estimates that the world will face another influenza pandemic -the only thing we don't know is when it will hit and how severe it will be. It also says that Influenza is an ever-evolving disease, so the work on prevention, preparedness and response has to adapt continuously to keep up with these changes.

Fragile and vulnerable settings

More than 1.6 billion people (22% of the global population) live in places where protracted crises (through a combination of challenges such as drought, famine, conflict, and population displacement) abound and weak health services leave them without access to basic care. Fragile settings exist in almost all regions of the world, and these are where half of the key targets in the sustainable development goals, including child and maternal health, remain unmet.

The need to strengthen health systems in fragile and vulnerable settings in imminent so that they are better prepared to detect and respond to outbreaks, as well as able to deliver high quality health services, including immunization.

Antimicrobial resistance

Antimicrobial resistance is the ability of bacteria, parasites, viruses and fungi to resist active medicines. This threatens to send us back to a time when we were unable to easily treat infections such as pneumonia, tuberculosis, gonorrhea, and salmonellosis. For example, the resistance to tuberculosis drugs is a formidable obstacle to fighting a disease that causes around 10 million people to fall ill, and 1.6 million to die, every year. Drug resistance is driven by the overuse of antimicrobials in people, and also in animals, especially those used for food production, as well as in the environment. The inability to prevent infections due to microbial resistance could seriously compromise surgery and procedures like chemotherapy.

WHO recommends that increasing awareness and knowledge about antimicrobial resistance, reducing infection, and encouraging prudent use of antimicrobials could help to tackle this issue. Moreover, the focus of healthcare associations to innovate next generation antibiotics would help in future preparedness.

Ebola and other high-threat pathogens

In 2018, the Democratic Republic of the Congo saw two separate Ebola outbreaks, both of which spread to cities of more than 1 million people. One of the affected provinces is also in an active conflict zone. This shows that the epidemic of a high-threat pathogen like Ebola erupts is critical, what happened in rural outbreaks in the past doesn't always apply to densely populated urban areas or conflict-affected areas.

In this view, WHO promotes its R&D Blueprint to identify diseases and pathogens that have potential to cause a public health emergency but lack effective treatments and vaccines. The WHO watch list for priority research and development includes Ebola, several other haemorrhagic fevers, Zika, Nipah, Middle East respiratory syndrome coronavirus (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS) and disease X, which represents the need to prepare for an unknown pathogen that could cause a serious epidemic.

Weak primary health care

Primary health care is usually the first point of contact people have with their health care system, and ideally should provide comprehensive, affordable, community-based care throughout life. WHO says that Healthcare systems with strong primary health care are needed to achieve universal health coverage, yet many countries do not have adequate primary health care facilities. Government efforts is needed to revitalize and strengthen primary health care in many countries.

Vaccine hesitancy

Vaccine hesitancy – the reluctance or refusal to vaccinate despite the availability of vaccines – threatens to reverse progress made in tackling vaccine-preventable diseases. Vaccination is one of the most cost-effective ways of avoiding disease – it currently prevents 2-3 million deaths a year, and a further 1.5 million could be avoided if global coverage of vaccinations improves.

Measles, for example, has seen a 30% increase in cases globally. The reasons for this rise are complex, and not all of these cases are due to vaccine hesitancy. However, some countries that were close to eliminating the disease have seen a resurgence.


Dengue is a mosquito-borne disease that causes flu-like symptoms and can be lethal. It kills up to 20% of those with severe dengue and has been a growing threat for decades. A high number of cases occur in the rainy seasons in countries such as Bangladesh and India. Over time the dengue season in these countries is lengthening significantly (in 2018, Bangladesh saw the highest number of deaths in almost two decades), and the disease is spreading to less tropical and more temperate countries such as Nepal, that have traditionally not seen the disease. An estimated 40% of the world is at risk of dengue fever, and there are around 390 million infections a year.


The progress made against HIV has been enormous in terms of getting people tested, providing them with antiretrovirals (22 million are on treatment), and providing access to preventive measures such as a pre-exposure prophylaxis (PrEP, which is when people at risk of HIV take antiretrovirals to prevent infection). However, the epidemic continues to rage with nearly a million people every year dying of HIV/AIDS. Since the beginning of the epidemic, more than 70 million people have acquired the infection, and about 35 million people have died. One of the solution to promote self-testing so that more people living with HIV know their status and can receive treatment (or preventive measures in the case of a negative test result).

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