More than 445,000 people were killed by malaria in 2016, and a shortage of funds has resulted in the fight against the disease stalling, according to a World Health Organization report.

There was a five million increase in the number of reported cases last year, rising from 211 million in 2015, the World Malaria Report 2017 added, with 57.3 million of those cases registered in Nigeria alone.

"We can safely say that after an unprecedented period of success, we are no longer making progress," Abdisalan Noor, lead author of the report, said.

"What is paramount now is taking this year's malaria report as a wake-up call to stimulate action."

Based on the report, 90 percent of the reported cases last year were in the African region, which also accounted for 91 percent of all malaria deaths in the same year.

The WHO said a minimum annual investment of $6.5bn was needed by 2020 to meet targets on controlling malaria by 2030.

Malaria Consortium, an NGO specialising in the control of the disease, echoed WHO's views, saying that with the shortfall in funds, it will be very difficult to reach the desired results.

"An increased funding would definitely help," James Tibenderana, global technical director at Malaria Consortium, told Al Jazeera.

"But I also feel that we need to work more with the private sector. Around 40 percent of the population affected has no access to the treatment. We either need to make diagnosis and treatment free of charge, or subsidise it.

"Without creating access, we will struggle to bring the figures down. We need to be smarter at how we use prevention methods and how we target them in the right places."

Nigeria accounted for more than 25 percent of the reported cases.

Fighting between the armed Boko Haram group and the Nigerian military left at least 20,000 people dead and more than 2.6 million displaced in the northeastern region.

More than half a million people were displaced in Nigeria last year, according to the Global Report on Internal Displacement. The mass displacement has also restricted access to healthcare and around two-thirds of health facilities were completely or partially destroyed.

"There was a two percent increase in the number of reported cases in Nigeria, and that's because malaria prevention activities weren't carried out due to funding issues," WHO's Rex Mpazanje told Al Jazeera.

"Some actions are being taken but it is important to note that the figures should reduce and if we can tackle the issue in Nigeria, this will also have a positive effect on the global figures."