Nigerians have been here before.

In November 2009, President Umaru Musa Yar’adua left the country for Saudi Arabia, seeking treatment for acute pericarditis brought on by a chronic kidney ailment. His health had been publicly declining for at least a year, and rumors that he was using a variety of international trips to secretly obtain medical treatment flourished in his frequent absences. Although he returned to Nigeria in late February 2010, he would never govern again, and was dead by May.

As former presidential spokesman Olusegun Adeniyi describes in his incredibly rich first-hand account Power, Politics & Death, the crisis that emerged from Yar’adua’s extended absence nearly sparked a constitutional crisis. During the roughly two months he was out of the country, reliable news about his status was scarce, and backroom political struggles over who exactly was running the country in his absence frequently spilled over into daily governmental affairs. Without a clear legal precedent, the National Assembly’s use of the “doctrine of necessity” to appoint then-vice-president Goodluck Jonathan as the “acting president” set off a chain of political events that eventually led to a coalitional breakdown in the ruling Peoples’ Democratic Party (PDP) and Jonathan’s electoral defeat in 2015 by Muhammadu Buhari.

So when President Buhari – who’d campaigned on cutting down the estimated $1 billion a year the Nigerian government pays towards government officials seeking medical care abroad – departed on January 19 for an “annual leave” in London, rumors began to swirl. And when, on February 6, his administration announced that following “routine examinations” he would be extending his stay to accommodate a “course of medications and further appointments,” the panic started to set in.

Maybe the only good news is that so far, Buhari’s absence hasn’t caused government to come crashing to a halt. The Nigerian constitution provides presidents the option of providing a written letter to the National Assembly declaring they’re ill or travelling on vacation, and appointing the vice-president as a legal “acting president.” Unlike Yar’adua, who failed to provide such a letter (apparently at the urging of his closest advisors, who feared making him appear weak) and kicked off a constitutional crisis in the process, Buhari has adhered strictly to the law. Twice before in 2016, he transferred power to Vice-President Yemi Osinbajo while travelling abroad on “vacation” or seeking medical treatment, and this time has been little different.

In Buhari’s absence, Osinbajo has led an official delegation to conflict-ridden regions of the Niger Delta, conducted cabinet business and met with visiting officials, and worked with the National Assembly on the 2017 Appropriations Bill. Meanwhile, Buhari is ostensibly continuing many of his duties from the Nigerian High Commission in London (unlike his predecessors, he’s forgone the expense of more luxurious hotel accommodations), including a phone call with U.S. President Trump that yielded a note of support for the controversial sale of 12 A-29 Super Tucano attack planes the Nigerian military want for the fight against Boko Haram. Yet despite these efforts, the Nigerian public remains largely in the dark.

There’s reason to be worried. Despite the optimism with which many Nigerians met Buhari’s ascendance, it’s been a rough 20 months. Officially, the naira’s lost roughly 50% of its value since the summer of 2016, but on the parallel market it’s lost closer to 250%. Oil prices have bounced back from their worst lows, but the administration continues to stare serious budget shortfalls in the face. Buhari’s vaunted promise to curb corruption has stalled, as those close to the administration seem to continue to receive more lenient treatment than its opponents. The war on Boko Haram continues, with attacks and bombings – and the ongoing humanitarian disaster across the northeast – dominating Nigeria’s international headlines. The government’s prompt handling of the mistaken bombing of an IDP camp by the Nigerian Air Force just days before Buhari’s “medical vacation” has drawn praise from some quarters, but it’s hard to imagine that the broader work of preventing another “mistake” can go forward without committed presidential involvement.

More broadly, it’s hard not to see the entire “medical vacation” affair through the lens of Buhari’s greatest weakness – his authoritarian tendencies. It’s been widely reported (but unconfirmed) that the president’s ailment is prostate cancer, and that the delay in his return is the result of complications with his chemotherapy regimen. But just as is the case with current U.S. national security policy, much of what Nigerians know about Buhari’s health comes from leaks and anonymous sources who have agendas of their own. Given many Nigerians’ suspicions about Buhari’s personal commitment to the messiness of democratic government, the administration’s lack of transparency has been shameful, and its shrill, tone-deaf response to the public’s concerns have done them no favors. Nigerians deserve more.