Stopping a polio outbreak in the midst of war: Lessons from Syria.

Background: Outbreaks of circulating vaccine-derived polioviruses (cVDPVs) pose a threat to the eventual eradication of all polioviruses. In 2017, an outbreak of cVDPV type 2 (cVDPV2) occurred in the midst of a war in Syria. We describe vaccination-based risk factors for and the successful response to the outbreak.

Progress Toward Poliomyelitis Eradication - Afghanistan, January 2018-May 2019.

Since October 2016, Afghanistan and Pakistan have been the only countries with reported cases of wild poliovirus type 1 (WPV1) (1). In Afghanistan, although the number of cases had declined during 2013-2016, the polio eradication program experienced challenges during 2017-2019. This report describes polio eradication activities and progress in Afghanistan during January 2018-May 2019 and updates previous reports (2,3).

Progress Toward Poliomyelitis Eradication - Pakistan, January 2017-September 2018.

Among the three wild poliovirus (WPV) serotypes, only WPV type 1 (WPV1) has been reported in polio cases or detected from environmental surveillance globally since 2012. Pakistan remains one of only three countries worldwide (the others are Afghanistan and Nigeria) that has never had interrupted WPV1 transmission. This report documents Pakistan's activities and progress toward polio eradication during January 2017-September 2018 and updates previous reports (1,2).

Progress Toward Poliomyelitis Eradication - Afghanistan, January 2017-May 2018.

Afghanistan, Pakistan, and Nigeria remain the only countries where transmission of endemic wild poliovirus type 1 (WPV1) continues (1). This report describes polio eradication activities, progress, and challenges to eradication in Afghanistan during January 2017-May 2018 and updates previous reports (2, 3). Fourteen WPV1 cases were confirmed in Afghanistan in 2017, compared with 13 in 2016; during January-May 2018, eight WPV1 cases were reported, twice the number reported during January-May 2017.

Strategic Response to an Outbreak of Circulating Vaccine-Derived Poliovirus Type 2 - Syria, 2017-2018.

Since the 1988 inception of the Global Polio Eradication Initiative (GPEI), progress toward interruption of wild poliovirus (WPV) transmission has occurred mostly through extensive use of oral poliovirus vaccine (OPV) in mass vaccination campaigns and through routine immunization services (1,2). However, because OPV contains live, attenuated virus, it carries the rare risk for reversion to neurovirulence. In areas with very low OPV coverage, prolonged transmission of vaccine-associated viruses can lead to the emergence of vaccine-derived polioviruses (VDPVs), which can cause outbreaks of paralytic poliomyelitis.

Progress Toward Poliomyelitis Eradication - Afghanistan, January 2016-June 2017.

Afghanistan, Pakistan, and Nigeria remain the only countries where the transmission of endemic wild poliovirus type 1 (WPV1) continues (1). This report describes polio eradication activities, progress, and challenges in Afghanistan during January 2016-June 2017 and updates previous reports (2,3). Thirteen WPV1 cases were confirmed in Afghanistan in 2016, a decrease of seven from the 20 cases reported in 2015.

Intracellular survival and replication of Neisseria meningitidis in human brain microvascular endothelial cells.

To cause meningitis the extracellular pathogen Neisseria meningitidis has to traverse the blood-cerebrospinal fluid (B-CSF) barrier. Postulating a transcellular passage, meningococci (MC) have been shown to adhere to and enter B-CSF barrier forming human brain microvascular endothelial cells (HBMEC). Furthermore, electron microscopy studies demonstrated that intracellular MC reside within membrane-bound compartments, both solitary and in groups.