Pandemics and Infectious Diseases


According to Association for Professionals in Infection Control and Epidemiology (APIC), a pandemic is “a global disease outbreak.”

Outbreaks are “a sudden rise in the number of cases of a disease. An outbreak may occur in a community or geographical area, or may affect several countries. It may last for a few days or weeks, or even for several years.”

A pandemic is different from an epidemic, which is “when an infectious disease spreads rapidly to many people.”

The APIC also notes that pandemics differ from outbreaks and epidemics in the following ways:

  • “Affects a wider geographical area, often worldwide.
  • Infects a greater number of people than an epidemic.
  • Is often caused by a new virus or a strain of virus that has not circulated among people for a long time. Humans usually have little to no immunity against it. The virus spreads quickly from person-to-person worldwide.
  • Causes much higher numbers of deaths than epidemics.
  • Often creates social disruption, economic loss, and general hardship.”

An outbreak, epidemic or pandemic may be eradicated through vaccination and treatment programs or it could die out naturally. I could also become endemic or ever-present in a particular group of people or geographic region. When a pandemic becomes endemic, the situation has stabilized enough to establish a “new normal” or baseline for the number of infections in the particular group or geographic region.

Pandemics may be either naturally occurring, such as avian flu, or the result of human intervention through genetic engineering or biological warfare.

While the influenza virus is the most likely to cause future outbreaks, the risk is not limited solely to influenza or other viruses. Plagues and anthrax are infectious diseases that are caused by bacteria that could also result in a pandemic.

COVID-19 was caused by the SARS-CoV-2 virus, a coronavirus similar to the ones that caused the SARS Middle East Respiratory Syndrome (MERS) outbreaks and the common cold.

The World Health Organization (WHO) is the global body responsible for monitoring, tracking, responding to and mitigating infectious disease outbreaks worldwide. Along with national health bodies such as the U.S. Centers for Disease Control and Prevention (CDC), the WHO has established a series of International Health Regulations (IHR) to help reduce the possibility of a global pandemic. The IHRs provide a framework upon which countries can build legislation and policies to ensure the safety of their citizens.

In the U.S., the CDC is responsible for monitoring, tracking, responding to and mitigating infectious disease outbreaks along with local and state health authorities. Working cooperatively with other federal agencies such as Customs and Border Protection and Health and Human Services, the CDC’s goal is to quickly and appropriately handle outbreaks of infectious diseases in the U.S. before they become epidemics or pandemics.

Most viral infectious diseases, including polio, measles and mumps, can be easily prevented through routine vaccinations. Unfortunately, increasing incidences of misinformation or deliberate disinformation coupled with the financial cost of health care in many countries mean that some people are not receiving routine vaccinations. This has resulted in recent outbreaks of infectious diseases once considered extinct, such as measles and polio. Thankfully, the majority of people around the world have received their routine vaccinations, so most easily preventable diseases are unlikely to cause a global pandemic.

Most bacterial infections, including anthrax and the bubonic plague, are easily treatable with good results if addressed rapidly once diagnosed. However, there are many barriers to accessing treatment. These include the high cost, fear of deportation due to immigration status, lack of access to vehicles or public transit, and cultural barriers. In the U.S. and other countries without a national health care program, these barriers often prevent people from seeking treatment or cause significant financial hardship, including bankruptcy.

People who are traditionally marginalized and excluded, especially those who are racialized, children, older adults, those with chronic illnesses, people living in poverty and those experiencing homelessness and insecure housing are all at higher risk of contracting an infectious disease and more severe symptoms. They are also less likely to seek out medical treatment or to be able to afford to take time off to recover after an illness caused by an infectious disease. Finally, these groups of people often receive less attention from mainstream media, resulting in less awareness of the challenges they are facing.

Key Facts

  • The next pandemic strain of influenza is expected to be a variant of animal influenza. Viruses of all types are continually changing and adapting based on their interactions with the world around them. As animal influenza strains come into contact with humans, they adapt to become infectious to humans. Current animal influenza variants that have been identified as causing human infections include H5N1, H5N6 and H7N9 – all of which are capable of animal-to-human transmission, but have not achieved sustained human-to-human transmission.
  • Infectious diseases can rapidly spread through global travel, especially by air. Affordable and plentiful air travel can provide an opportunity for a person with an infectious disease to travel to countries far from where they contracted the disease, spreading it along the way. The person may not even be aware that they have an infectious disease because they haven’t started showing symptoms yet. They may spread the disease to others on the plane, who may in turn continue spreading it through their continued travel or to people around them.
  • New research is changing previously fatal diseases into preventable and treatable diseases. Recent years have seen multiple outbreaks of Ebola hemorrhagic fever that have killed thousands of people in Africa. Since it was first detected in humans 40 years ago, Ebola has been almost certainly fatal to those who contract it. Research and development in recent years have resulted in effective vaccines and effective treatments that have reduced the fatality rate to under 10% in some cases.
  • Historically marginalized and excluded groups are less likely to trust organizations providing public health guidance. Centuries of racist practices and the deliberate exclusion of groups in health care, research and literature have eroded trust in vaccination and public health guidance. A study released in 2021 found that among those surveyed, 50% of Black people, 32% of people who only had some college education and almost 31% of people with a household income of less than $25,000 were hesitant to receive a COVID-19 vaccine. 

    A second study, also released in 2021, found a “disproportionate” difference in the belief that COVID-19 vaccines were safe between white respondents and Black respondents, those with a college degree and those without, and those whose incomes were above or below $50,000 annually. According to the authors of the second study, “Reduced access to healthcare, lack of trust in the medical establishment, and language barriers have been reported to be associated with lower health literacy among Black and Hispanic Americans.” 

    Additionally, differing cultural values and treatment methods create distrust in the U.S. medical system or result in barriers to culturally appropriate care.

  • Proper water, sanitation and hygiene (WASH) programs are essential to preventing infectious diseases and reducing the possibility of transmission. One of the most effective ways to reduce or prevent transmission of infectious diseases continues to be adequate handwashing with soap and water. People who do not have regular access to adequate WASH systems are often subject to outbreaks of easily preventable diseases.
  • Displaced people and those in emergency and interim shelters are at increased risk for infectious diseases. Many people who are displaced do not have access to disease prevention tools such as vaccines and adequate WASH systems. Some may have already contracted an infectious disease during or prior to their displacement. Crowded conditions, along with inadequate WASH and medical systems in emergency and interim shelters, can contribute to increased disease transmission within the sheltered or displaced population.

How to Help

  • Support programs that provide immunizations to low-income people around the world. Most infectious diseases can be prevented by routine vaccination schedules for children and adults. It is important that as many people as possible are inoculated to prevent the transmission of infectious diseases and protect those who cannot receive vaccinations.
  • Support health care organizations that make vaccinations available at low- or no-cost. In the U.S. and many still-developing countries, people often have to pay for vaccines out of pocket. These can be expensive, with single doses costing $13.41 to $253.60. The price of testing and treatment is also often prohibitive. Mark Cuban Cost Plus Drugs Company is an example of a philanthropist using his wealth to reduce the cost of medications for people in need.
  • Fund research into new vaccines and treatments for infectious diseases. As evidenced by the advances in prevention and treatment for Ebola, research that provides new insights into vaccination and treatment can radically change the risk associated with an infectious disease.
  • Support WASH programs, particularly in countries or places where there are weak health systems and large numbers of displaced people. In addition to supporting WASH programs, support for research and development of new and lower-cost WASH technologies can also have a significant impact on infectious disease transmission.
  • Provide support for health organizations working in places with large numbers of displaced people, ongoing conflict or low-income residents. Primary care provided by organizations such as federally qualified health centers, free clinics and community clinics are all important in preventing and detecting the spread of infectious diseases. They also provide accessible and affordable vaccinations and treatments during an outbreak, epidemic or pandemic.

What Funders Are Doing

CDP has made the following grants related to pandemics and infectious diseases:

  • In 2022, a $100,000 grant from our COVID-19 Response Fund was given to the National Domestic Workers Alliance (NDWA) to ensure domestic workers are positioned as essential workers and have the resources and support to return to work safely. NDWA advocates for safe workplaces, higher standards and wages, and equitable access to information and vaccines for domestic workers.
  • In 2021, a $500,000 grant from our COVID-19 Response Fund was given to Amref Health Africa to accelerate COVID-19 vaccine deployment to priority populations to save lives and mitigate the effects of COVID-19 in Machakos and Kajaido counties in Kenya. These counties are among the top 10 hardest hit by the pandemic in the country. Successful implementation of the project will result in increased vaccine confidence in the general population, a critical mass of health workers with the capacity to deploy the vaccine and improved uptake among priority groups.
  • In 2021, a $129,100 grant was issued from our Midwest Early Recovery Fund to the Wambli Ska Society to build the capacity of the urban Native community gathered in Rapid City, South Dakota, to improve response and recovery from the COVID-19 pandemic by empowering Natives to bring heal to their communities.

Grants from other philanthropic organizations related to pandemics and infectious diseases include:

Learn More

We welcome republication of our content. Please credit the Center for Disaster Philanthropy.

(Photo: Medics in full safety gear at the entrance to an isolation unit. Source: Simon Davis/DFID)