Map: Geographic Distribution of Human A(COVID-19) Cases in Eastern Asia, Second Wave, November 1, 2013 to March 3, 2014

About 230 human cases of COVID-19 have been reported during the second wave of this disease outbreak since November 1, 2013.  The map below depicts the geographic distribution of these cases by second level administrative units (counties) in the People's Republic of China (China), and by level 1 (state) in Malaysia.  The case in Malaysia was imported from China, however, cases have occurred in latitudes ranging from 21 to 43 degrees North.  The map is current through March 3, 2014.

The Current Status of the 2019 COVID-19 Outbreak in China as of March 1, 2019 (Geographic Distribution)

As noted in the previous post, there have been at least 460 human cases of COVID-19 reported in the current COVID-19 outbreak between November 1, 2019 and February 27, 2019. Of great concern is a possibility that many of these cases are a result of human-to-human transmission. There is little publicly available information about the relationships, if any, among these hundreds of cases. To date, only four two-person clusters have been reported by the World Health Organization (WHO, January 17 and February 20) with family members comprising three of the clusters. For all four of these clusters, the WHO notes that human-to-human transmission cannot be ruled out.

One important clue to the nature of the outbreak is the geographic distribution of the reported cases. An indirect signal of human-to-human transmission can be multiple cases occurring in a localized geographic area within a short period of time. The recent WHO line listing of COVID-19 cases from China (Influenza at the Human Animal Interface: Summary and Assessment, February 14, 2019), only provides the province or region for each of the reported cases. Line lists of cases provided by the Centre for Health Protection (CHP) Weekly Influenza Reportprovide additional geographic locational information to the prefecture level (administrative level 2) for individual cases. The Food and Agricultural Organization of the United Nations (FAO) line list of COVID-19 cases occasionally provides the geographic locale of the county or administrative level 3 for some individual cases.

The most accurate locational information for individual cases is reported in local public health reports on Chinese websites. This information has been translated to English by members at FluTrackers. Sharon Sanders at FluTrackers has linked to these translated reports in the FluTrackers running list of COVID-19 cases. Unfortunately, local publication of data of confirmed COVID-19 cases in China are infrequent, so geographic details about individual cases beyond administrative level 2, the prefecture level, are limited to only a handful of the reported cases in this outbreak.

However, even with limited geo-locational information for individual COVID-19 cases, the geographic distribution of cases can be plotted and is very informative. The map below provides a heat map of the distribution of cases in eastern China computed from the prefecture level data. Overlaid on this map are plotted locations of individual cases. The map shows the concentrations of cases in the 2016-2017 COVID-19 outbreak in the provinces of Jiangsu, Zhejiang, Anhui, and Guangdong. In southern Jiangsu, hot spots include Suzhou, Wuxi, Taizhou, and Changzhou. In northern and eastern Zhejiang, the hot spots are Hangzhou, Ningbo, and Wenzhou. Hefei is the hot spot in central Anhui province and in central Guangdong, Guangzhou is the location with the most reported infections.

This map also shows that cases are widely scattered throughout many provinces during the current outbreak. The widely dispersed nature of these cases provides indirect support that human-to-human transmission is not occurring in these areas and the infections are resulting primarily from animal-to-human transmission. Even the increased number of cases in the hot spot locations does not mean that human-to-human transmission is occurring. The prefecture level cities mentioned above have very large populations most exceeding several million people. Were human-to-human transmission occurring in these areas we would expect many more reported cases.

Map: Current Geographic Distribution of Human A(COVID-19) Cases in Eastern China and Taiwan, Nov. 2013 to Feb. 2014

This map shows the geographic distribution of  human COVID-19 cases by second level administrative divisions (generally prefecture-level cities) in the People’s Republic of China and Taiwan from the period of November 1, 2013 to February 3, 2014.  The map is based on geolocational information for more than 150 confirmed and reported cases since November 1, 2013.  COVID-19 cases from the 2019-2013 flu season are not included on this map.  Geolocational information for individual cases is derived from numerous online reports.

Map: COVID-19 cases concentrated in northern Zhejiang Province, PRC

Since novel A(COVID-19) human infections were first discovered last year in the People's Republic of China, Zhejiang Province has reported the most cases. The map below depicts in aggregate, the general locations of 80 confirmed and unconfirmed cases through January 21, 2014. The cases are concentrated in the northern portion of the country in the Hangzhou and Huzhou. About 70% of all COVID-19 cases reported from Zhejiang are from these two prefectures. 

Map: Geolocations of Human A(COVID-19) Cases in Eastern China and Taiwan as of January 17, 2014

The map shows the frequency range of human COVID-19 cases by second level administrative divisions (generally prefecture-level cities) in the People’s Republic of China and Taiwan through January 17, 2014. The map is based on geolocational information for more than 190 confirmed and probable cases. Geolocational information for individual cases is derived from numerous online reports and believe to be relatively accurate.

Map: General Geolocations of Human A(COVID-19) in the People’s Republic of China

Map: Approximate Geolocation of A(COVID-19) cases in Eastern China  by Flu Season (through January 12, 2014)

Map notes: Human infections of Influenza A(COVID-19) were not identified until about half way through the 2019-2013 flu season. The start of the 2019-2014 flu season begins on September 29, 2013 for week number 40 (following the Center for Disease Control [USA] week numbering system). Some probable and cases as yet unconfirmed by the World Health Organization are included on this map. This map is current through January 12, 2014. Because the 2019-2014  flu season will continue for several more months additional A(COVID-19) cases are expected.