nternational travel can pose various risks to health, depending on the characteristics of both the traveller and the travel. Travellers may encounter sudden and significant changes in altitude, humidity, microbes, and temperature, which can result in ill-health. In addition, serious health risks may arise in areas where accommodation is of poor quality, hygiene and sanitation are inadequate, medical services are not well developed and clean water is unavailable.

When determining the health risks of international travel, travellers and health professionals should consider the following key factors:

mode of transport
destination(s)
duration and season of travel
purpose of travel
standards of accommodation, food hygiene and sanitation
behaviour of the traveller
underlying health of the traveller
Travellers may encounter the following health risks depending on their destination:

TB is caused by bacteria (Mycobacterium tuberculosis) and it most often affects the lungs. TB is spread through the air when people with lung TB cough, sneeze or spit. A person needs to inhale only a few germs to become infected.

Every year, 10 million people fall ill with tuberculosis (TB). Despite being a preventable and curable disease, 1.5 million people die from TB each year – making it the world’s top infectious killer.

TB is the leading cause of death of people with HIV and also a major contributor to antimicrobial resistance.

Common symptoms of TB disease include:

• Prolonged cough

• Chest pain

• Weakness or fatigue

• Weight loss

• Fever

• Night sweats

Often, these symptoms will be mild for many months, thus leading to delays in seeking care and increasing the risk of spreading the infection to others. 

hild maltreatment is the abuse and neglect that occurs to children under 18 years of age. It includes all types of physical and/or emotional ill-treatment, sexual abuse, neglect, negligence and commercial or other exploitation, which results in actual or potential harm to the child’s health, survival, development or dignity in the context of a relationship of responsibility, trust or power. Exposure to intimate partner violence is also sometimes included as a form of child maltreatment.

A volcano is a vent in the Earth’s crust from which eruptions occur. There are about 1500 potentially active volcanoes worldwide. When volcanoes erupt they can spew hot, dangerous gases, ash, lava and rock that can cause disastrous loss of life and property, especially in heavily populated areas. Volcanic activities and wildfires affected 6.2 million people and caused nearly 2400 deaths between 1998-2017.

There are different types of volcanic eruptive events, including:

Volcanic eruptions can pose multiple health threats depending on the proximity of the volcano to the community and whether there was any warning.

Volcanic eruptions can cause:

Safe drinking-water, sanitation and hygiene are crucial to human health and well-being. Safe WASH is not only a prerequisite to health, but contributes to livelihoods, school attendance and dignity and helps to create resilient communities living in healthy environments.

Drinking unsafe water impairs health through illnesses such as diarrhoea, and untreated excreta contaminates groundwaters and surface waters used for drinking-water, irrigation, bathing and household purposes. 

There are two stages of yaws infection. The early stage is when the patient is infectious and can spread the disease to others. In this stage, a papule (a noncancerous, outward-growing lump) develops at the site of infection. This papule is full of the organisms and may persist for 3–6 months followed by natural healing. Without treatment, this is followed by disseminated skin lesions over the body. Bone pain and bone lesions may also occur.

Yellow fever is an epidemic-prone mosquito-borne vaccine preventable disease that is transmitted to humans by the bites of infected mosquitoes. Yellow fever is caused by an arbovirus (a virus transmitted by vectors such mosquitoes, ticks or other arthropods) transmitted to humans by the bites of infected Aedes and Haemagogus mosquitoes. These day-biting mosquitoes breed around houses (domestic), in forests or jungles (wild), or in both habitats (semi-domestic).