Global Infectious Diseases in August 2023: A Monthly Analysis

Infectious diseases frequently affect children and adults worldwide. Owing to their specific biology and mode of transmission, the presence of infected individuals or carriers in a region often leads to outbreaks of the disease in that region, and in severe cases, to the death of the infected individual. Infectious diseases have been one of the main causes of mass disability or death in humans for centuries. Surveillance of infectious diseases on a continental scale is therefore important for assessing, recognizing, and preventing the risks that these diseases may pose to animal and human health on a global scale. This report focuses on global infectious disease outbreaks and systematically summarises the timing and location of outbreaks in infected populations between 24 July and 23 August 2023 based on the Global Outbreak Information Surveillance System (GOSIS) of Shusi Technologies.


INTRODUCTION
Due to the unbalanced density of the population and exposure to virulent diseases, infectious diseases have accompanied human development since ancient times, often causing epidemics and daily infections to vulnerable populations.Having demonstrated that microorganisms are the primary cause of human disease, we have made great strides in understanding how pathogens cause disease and in developing therapies to prevent and treat infections.Such revolutionary treatments include improvements in hygiene, the development of vaccines to prevent infections, the creation of pathogen-specific tests to diagnose disease, and the design of antimicrobial agents that then treat patients.Relying on the development of vaccines and medicines, the burden of infectious diseases has been greatly reduced.Despite such successes, the swine fever of 2009, the Middle East Respiratory Syndrome coronavirus of 2012, Ebola virus of 2013-2016, the Zika virus of 2015, and the new coronavirus sweeping the globe in 2019 are evidence that infectious diseases are still the leading cause of morbidity and mortality today, even at a time when the economy and medical care have improved dramatically.
The journal "ZOONOSES" compiles and analyzes the development of global infectious diseases.The development of global infectious diseases is compiled and analyzed by regularly compiling and analysing information and visualizing the distribution of diseases.Using the Global Outbreak Information Surveillance System (GOSIS), other infectious disease types with relatively low incidence rates were analyzed for the period July 24, 2023 to August 23, 2023 (Fig 1).

COVID-19
The coronavirus disease 2019 (COVID-19) pandemic, which was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), continues to ravage the world due to the emergence of the omicron variant and its descendant subvariants.While BA.5 is currently the dominant subvariant globally, a range of different omicron subvariants have emerged and are competing in the so-called 'variant soup.' BQ.1 and BQ.1.1 were first detected in Nigeria in early July 2023, and have since spread across Europe and North America.XBB and XBB.1 were first detected in India in mid-August 2023 and have rapidly spread across India, Singapore, and other parts of Asia [1].Globally, there was little change in the overall number of cases last month (24 July 2023 to 23 August 2023), with the total number of people living with the disease decreasing compared to the previous year.Europe still accounts for the majority of new cases in the affected population; however, there was a slight decrease in the number of people living with the disease in Europe compared to the previous month.As of August 2023 greater than 753 million confirmed cases and greater than 6.76 million deaths have been reported worldwide (Fig 2 ).

MONKEYPOX (MPOX)
Two cases of Mpox virus infection in humans returning to the United States from Nigeria have been reported and found since 2021, with one of the infected individuals returning to Texas ( July 2021) and the other returning to Washington, D.C. (November 2021) [2].Shortly after these two cases were reported, the number of cases continued to climb.All cases have been associated with international travel or imported animals from Africa.While epidemics of the virus are more common in central and western Africa, the prevalence in developed countries has triggered troubling signs of global spread.As of August 2023, the number of new cases of Mpox in developed countries has continued to climb, with the total number of cases in developed countries increasing to 7565 in Spain, 4150 in France, and 3694 in Germany.The number of cases in the rest of the developing world included 557 in Ecuador, 10 in Taiwan, China, and 3 in Hong Kong, China (         The smallpox vaccine has the potential to provide some protection against Mpox infection due to the genetic similarity [5].Considering the route of transmission of Mpox virus and the high incidence, isolation of patients who have been infected with Mpox is needed, and vaccination may be considered to help prevent Mpox infection in at-risk populations.

CHOLERA
Cholera is a virulent infectious disease caused by the bacterium, Vibrio cholerae.Cholera is an acute gastrointestinal illness that is often fatal.The typical epidemiologic form of the disease often presents as mild-to-potentially fatal acute watery diarrhoea, which in severe cases leads to severe dehydration and ultimately death within hours in undiagnosed patients.Prompt rehydration therapy with the use of antimicrobial drugs is the basis of treatment [6].Two serogroups of V. cholerae (O1, to which the El Tor biotype belongs, and O139) are the main subgroups causing endemic cholera.Vibrio cholerae is excreted in the faeces of infected individuals and often contaminates water sources in places with poor sewerage systems, thus causing endemic cholera outbreaks.Since the 1991 cholera outbreak in the Americas, the World Health Organisation (WHO) estimated that the population at risk for cholera will reach a staggering 1.4 billion people; thus, almost all developing countries will be at risk for cholera [7].Historically, cholera was endemic in the Asian subcontinent (i.e., India, Indonesia, Vietnam, and Bangladesh), but now cholera is endemic in Africa, Zambia, Sierra Leone, Nigeria, Angola, the Democratic Republic of Congo [DRC], Zimbabwe, the United Nations of Santanya, Yemen, Latin America, and the Caribbean (including Haiti, Cuba, and the Dominican Republic) [8]

DENGUE
Dengue is an insect-borne infection caused by one of the dengue viruses (DENV-1-4) transmitted by Aedes aegypti mosquitoes and is endemic in tropical and subtropical regions.Infection with DENV often results in patients presenting with clinical symptoms, such as nausea, vomiting, headaches, arthralgias and myalgias, and skin rashes.
In the absence of effective prevention and control measures, the geographic scope and disease burden of dengue will increase [9].Since the summer season, there has been a gradual increase in the number of cases in tropical and subtropical regions, especially in countries in the tropics, with 11,433 cases in Brazil, 85,692 cases in the Philippines, 60,136 cases in Sri Lanka, 59,372 cases in Thailand, 57,295 cases in Vietnam, 14,583 cases in the Republic of Bangladesh, and 124,999 cases in Nepal as of August 2023 (Table 3).Dengue fever is a self-limiting disease, although there is currently no clear treatment plan, but severely ill patients should be provided with individualised treatment, often based on intravenous rehydration, hormonal anti-inf lammatories, and platelet transfusion for patients with severe bleeding [10].The chimeric yellow fever dengue vaccine using yellow fever virus (YFV) strain 17D as the replication backbone (Chimerivax DEN; CYD-TDV) has been shown to have an overall combined protective efficacy of 65.6% and has been tested for safety and immunogenicity [11].

MEASLES
Measles is an acute viral infection caused by the measles virus, which is a seasonal disease in endemic areas.Transmission is mainly person-to-person through respiratory droplets in the air, but also through direct contact with infected secretions [12].The incubation period for measles is usually 10-14 days, with symptoms often manifesting as fever, malaise,   [13].In the context of a significant decline in global measles virus deaths, the number of measles deaths globally fell from 535,300 in 2000 to 139,300 in 2010 (a 74% decrease) [14].There are still geographic areas with poor sanitation, a lack of good medical resources, and difficulties in universal vaccination that have a relatively large number of measles cases, such as the Democratic Republic of the Congo and Liberia (Table 4).

INFLUENZA
Influenza, also known as the flu, is a highly contagious respiratory disease caused by a variety of RNA influenza viruses that infect humans.Complications from influenza can lead to severe morbidity and mortality.Globally, up to 500,000 people die each year from complications of influenza.Since 2010, the CDC has estimated that seasonal influenza infections have resulted in 9.3-45 million cases, 140,000-810,000 hospitalisations, and 12,000-61,000 deaths annually in the United States [14].In the United States and all countries in the northern hemisphere, the influenza season usually begins in late October and continues through May.As of August 2023, countries in the northern hemisphere, such as France and Switzerland, and Australia in the southern hemisphere, still have a high number of infections, even after the common season for influenza has passed (Table 5).The severity of influenza each year depends on the spread and characteristics of the influenza virus, the availability and vaccination rate of effective vaccines against the current pandemic strains, the host's immune response, and the presence or absence of co-morbidities in the individual [15].Because of the high rate of mutation of influenza viruses, although influenza is prevented by vaccination of susceptible individuals, antiviral medications and prompt symptomatic treatment are always the cornerstone of treatment.

CHIKUNGUNYA VIRUS
Chikungunya virus (CHIKV), an Old World alphavirus belonging to the Togaviridae family of arboviruses, contains an RNA genome and is transmitted through mosquito bites (mainly Aedes aegypti, but also Aedes albopictus) [16].There are three main genotypes of CHIKV (west African, east-south central Africa [ECSA], and Asian) and a fourth lineage belonging to ECSA (the Indian Ocean lineage) [17].Sporadic outbreaks are currently being reported around the world, mainly in Africa, Asia, the Indian Ocean and Pacific regions, Europe, and recently even in the Americas.As of August 2023, the number of cases in Argentina and Brazil have decreased to varying degrees from the previous period, but the number of patients in Paraguay is still rising, along with a gradual increase in the number of fatal cases (Table 6).Symptomatic treatment with antipyretics, analgesics, and massive rehydration, as well as non-steroidal anti-inf lammatory drugs (NSAIDs), hydroxychloroquine, corticosteroids, and disease-modifying anti-rheumatic drugs (DMARDs), are used to improve symptoms in viral arthritis.

POLIOMYELITIS
Polio is a serious and highly contagious disease that can affect the central nervous system.Polio, also known as poliomyelitis, is an infection caused by a virus (poliovirus).Polio usually affects children ≤ 5 years of age.Polio can cause muscle weakness, permanent disability, and even death.Polio is rare in the United States because the vaccine against polio is part of routine childhood immunisation.The polio virus is highly contagious and is easily spread through person-to-person contact.The virus is usually present in the throat of an infected person for 1-2 weeks and is excreted in the faeces for 3-6 weeks, even in asymptomatic people.Poliovirus enters the body through the mouth, and the most common mode of infection is through contact with the faeces of an infected person or through contaminated food or water.Poliovirus can also be transmitted through saliva and respiratory droplets.Global vaccination efforts have been in place since the 1980s, and as a result polio is considered to be completely eradicated to date, although there are still cases of the virus in areas with poor sanitary and medical conditions.As of August 2023, there have been sporadic reports in some countries in Africa, including the Democratic Republic of the Congo, Nigeria, and the United Republic of Tanzania (Table 7).

CONCLUSION
In the modern world of large interconnected populations and rapid transport, where the potential for global spread of infectious diseases is extremely high, international cooperation in the surveillance, prevention, and control of infectious diseases is essential.The experience with new coronaviruses and the devastating pandemics of inf luenza and AIDS in the last century have focused on the threat posed by new pathogens.The number of Mpox cases in developed regions continues to rise considerably.Although there is no distinct season for the high incidence of cholera, July to October each year is still the period in which the incidence of cholera is high.Since entering the summer, the number of people suffering from dengue fever in tropical and subtropical areas has gradually increased.With the introduction of polio and measles vaccines, these two diseases have been eradicated in many countries, but are still prevalent in a few African regions due to limited medical resources.SARS-Cov-2 has caused very serious illnesses, and the diseases caused by this strain have resulted in high mortality rates and large-scale social, cultural, and economic upheavals.Preventing outbreaks and related pandemics is therefore a global challenge.This is especially true for countries and regions with low health and economic capacity.At the same time, as pathogens evolve, so do the diagnostic methods.The first CRISPR diagnostic system received FDA Emergency Use Authorisation for the diagnosis of SARS-CoV-2 in the US in 2020.More importantly, countries and regions must have robust healthcare systems in place so that they are able to provide healthcare to sufficient populations during a pandemic.

FIGURE 2 |
FIGURE 2 | Global daily statistics on the number of new confirmed cases and deaths due to new cases of coronavirus pneumonia.A,C: New cases and deaths of COVID-19 reported daily for each continent.B,D: Specific proportions of new confirmed cases and deaths due to COVID-19 for the European continent (24 July 2023 to 23 August 2023; data from the WHO website: https://COVID19.who.int/).

TABLE 1
[4]the disease ranges from 1% -10%[4].Mpox virus infection is usually mild and most patients recover without treatment.For patients with severe symptoms of Mpox, treatment with cidofovir (Vistide) is recommended
. As of August 2023, with the arrival of the high cholera season, the incidence of the disease has shown explosive growth in all regions, with 58,982 cases in Malawi, 58,629 cases in Haiti, 33,862 cases in Mozambique Mauzaro, 31,342 cases in the Republic of the Congo, 17,007 cases in Ethiopia, and 11,941 cases in Kenya (Table 2).

TABLE 4 |
Worldwide measles cases reported between 23/07/2023 and 24/08/2023., conjunctivitis, and cough, with the characteristic rash appearing 2-4 days after the appearance of early symptoms or an aura.Prior to the introduction of measles vaccine in 1963, large epidemics have occurred approximately every 2-3 years.It is estimated that there are 30 million cases of measles and greater than 2 million deaths worldwide each year cough