JOHANNESBURG, South Africa —  President Trump has tested positive for the coronavirus, joining a small group of world leaders who have been infected. Trump is 74, putting him at higher risk of serious complications. Here’s a look at other leaders who have been infected.

Boris Johnson

The British prime minister was the first major world leader confirmed to have COVID-19. He was moved to intensive care in April when his virus symptoms dramatically worsened a day after he was hospitalized for what were called routine tests. He was given oxygen but did not need a ventilator, officials said. He later expressed his gratitude to National Health Service staff for saving his life when his treatment could have “gone either way.” Prince Charles, the heir to the British throne, also tested positive in March and came down with mild COVID-19 symptoms.

Jair Bolsonaro

The Brazilian president announced his illness in July and used it to publicly extol hydroxychloroquine, the unproven malaria drug that he’d been promoting as a treatment for COVID-19 and was taking himself. For months he had flouted social distancing at lively demonstrations and encouraged crowds during outings from the presidential residence, often without a mask.

Juan Orlando Hernandez

The Honduran president announced in June that he and his wife had tested positive, along with two other people who worked closely with them. Hernandez said he had started what he called the “MAIZ treatment,” an experimental and unproven combination of microdacyn, azithromycin, ivermectin and zinc that his government was promoting as an affordable way of attacking the disease. He was briefly hospitalized and released in July. Hernandez has added his voice to growing pleas for equitable access to any COVID-19 vaccine, asking the recent U.N. gathering of world leaders, “Are people to be left to die?”

Alexander Lukashenko

The president of Belarus, who dismissed concerns about the virus as “psychosis” and recommended drinking vodka to stay healthy, said in July he had contracted it himself but was asymptomatic. Belarus is one of the few countries that took no comprehensive measures against the virus. Other top officials in former Soviet states who were infected include Armenian Prime Minister Nikol Pashinyan and Russian Prime Minister Mikhail Mishustin.

Prince Albert II of Monaco

The palace of Monaco in March said the ruler of the tiny Mediterranean principality tested positive but his health was not worrying. He was the first head of state who publicly said he was infected.