Altitude Risk: Nigeria Cautions Citizens Against Travelling via Addis Ababa

Nigeria's government has cautioned its citizens, in particular those with medical conditions, against travelling via Ethiopia's main airport, saying the airport's altitude is the reason for the warning.

In a statement from the capital Abuja, the foreign ministry said 16 Nigerians with underlying health problems had died this year while transiting through Addis Ababa.

Addis Ababa sits at an altitude of 2,334 metres (7,657 feet) above sea level, making it one of the highest capitals in the world. The city's Bole International Airport is a major hub for travel between Africa, the Middle East and Asia, serving millions of passengers a year.

Nigeria said those with cardiovascular and respiratory conditions were at an increased risk at that altitude.

The foreign ministry did not, however, disclose the identities of the travellers it said had died, nor the cause of death.

It urged anyone with a health condition exacerbated by high altitudes to exercise caution when planning a journey via Addis Ababa and to obtain appropriate medical guidance before doing so.

At the same time, the ministry stressed that it did not want to discourage Nigerians from travelling through the Ethiopian capital.

Experts say that at high altitude the air is thinner, so less oxygen can get into the bloodstream. That means the heart has to work harder to get enough oxygen to different parts of the body, which can sometimes lead to heart failure among those with existing conditions, according to the American Heart Association.

Studies show the lack of oxygen at high altitudes can cause adverse effects such as dizziness, fatigue and shortness of breath among healthy people, which can cause complications for people with lung disease.