In the Vietnamese measles epidemic in spring of 2014, an estimated 8,500 measles cases were reported as of 19 April, with 114 fatalities; as of 30 May, 21,639 suspected measles cases had been reported, with 142 measles-related fatalities. In the Naga Self-Administered Zone in a remote northern region of Myanmar, at least 40 children died during a measles outbreak in August 2016 that was probably caused by lack of vaccination in an area of poor health infrastructure. Following the 2019 Philippines measles outbreak, 23,563 measles cases have been reported in the country with 338 fatalities. A measles outbreak also happened among the Malaysian Orang Asli sub-group of Batek people in the state of Kelantan from May 2019, causing the deaths of 15 from the tribe. A measles outbreak in New Zealand has 2193 confirmed cases and two deaths. A measles outbreak in Tonga has 612 cases of measles. A measles outbreak in Samoa in late 2019 has over 5,700 cases of measles and 83 deaths, out of a Samoan population of 200,000. Over three percent of the population were infected, and a state of emergency was declared from November 17 to December 7. A vaccination campaign brought the measles vaccination rate from 31–34% in 2018 to an estimated 94% of the eligible population in December 2019. The Democratic Republic of the Congo and Madagascar have reported the highest numbers of cases in 2019. However, cases have decreased in Madagascar as a result of nationwide emergency measles vaccine campaigns. As of August 2019 outbreaks were occurring in Angola, Cameroon, Chad, Nigeria, South Sudan and Sudan. An outbreak of measles in 2018 has resulted in 118,000 cases and 1,688 deaths. This followed outbreaks of bubonic and pneumonic plague in 2017 (2575 cases, 221 deaths) and 2014 (263 confirmed cases, 71 deaths). An outbreak of measles with nearly 5,000 deaths and 250,000 infections occurred in 2019, after the disease spread to all the provinces in the country. Most deaths were among children under five years of age. The World Health Organization (WHO) has reported this as the world's largest and fastest-moving epidemic. Most estimates based on modern molecular biology place the emergence of measles as a human disease sometime after AD 500 (the former speculation that the Antonine Plague of AD 165–180 was caused by measles is now discounted), although recent studies suggest measles potentially first appeared as early as the 4th century BC. The first systematic description of measles, and its distinction from smallpox and chickenpox, is credited to the Persian physician Rhazes (860–932), who published "The Book of Smallpox and Measles".