Global health. The current scenario and future perspectives

144 in local surveillance systems at the country level. The global response to public health emergencies and the monitoring and evaluation system of the International Health Regulations (IHR) (WHO, 2005) is integrated through the Global Outbreak Alert and Response Network (GOARN). The GOARN is a mechanism of technical collaboration between institutions and networks that pool their human and technical resources to respond to health alerts and disasters worldwide. It consists of over 250 technical institutions and networks in more than 90 countries, including various United Nations organizations, humanitarian aid NGOs and representations of health ministries of countries adhering to the IHR. The IHR, approved in 2005 and implemented in 2007, is an international consensus to prevent, protect, control and provide a public health response to risks related to epidemic outbreaks through a set of recommendations for international mobility in health emergencies (people, luggage, cargo, containers, transportation, postal packages, etc.). It establishes the basic rules for controlling different points of entry into countries (airports, ports, land border crossings), public health measures for travelers and various health documents. The Director-General of the World Health Organization and its Advisory Committee and Independent Oversight for the WHO Health Emergencies Program determine whether a health emergency is a Public Health Emergency of International Concern (PHEIC). This is defined as “an extraordinary event which is determined to constitute a public health risk to other States through the international spread of disease and to potentially require a coordinated international response” according to the International Health Regulations (IHR). When a PHEIC is declared globally, the primary objective is to ensure health security through the implementation of the IHR. Therefore, the entire global alert and response system of the WHO ensures event surveillance, rapid risk assessment, communication of necessary information for decision-making and effective coordination of response activities. Since the implementation of the IHR in 2007, six PHEICs have been declared worldwide: Pandemic Influenza A (H1N1) in April 2009; international spread of wild poliovirus in May 2014; Ebola virus disease outbreak in West Africa in August 2014; a group of cases of congenital malformations and other neurological disorders associated with Zika virus in February 2016; Ebola-virus disease outbreak in the Democratic Republic of the Congo in October 2019; and the Covid-19 pandemic caused by the SARS-CoV-2 virus in Wuhan, China, in January 2020. From a historical perspective, although public health surveillance can be traced back thousands of years, the modern concept of surveillance