PRI’s MPV (Monkeypox) Situation Update – September 13

Sep 13, 2022 | News

Latest editions Tuesday and Thursdays. While we use the language “MPV”, most sources do not, and readers will see the language fluctuate within the report. For questions and feedback, please email


Case Counts/Trends and Large Guidance/Response Changes (Limited by latest reporting)

  • GLOBAL: From 1 January through 4 September 2022, 52 996 laboratory-confirmed cases of monkeypox and 18 deaths have been reported to WHO from 102 countries/territories/areas in all six WHO Regions (Table 1). Since the last edition of this report published on 24 August 2022, 11 332 new cases (27% increase) and six new deaths were reported; and six new countries reported cases. In the past seven days, 25 countries reported an increase in the weekly number of cases, with the highest increase reported in Colombia, and one country, South Sudan, reported its first case (29 August 2022). There are 27 countries that have not reported new cases for over 21 days, the maximum incubation period of the disease. (WHO Sit Rep – Latest 9/7/2022 / Dashboard)
  • US: Total confirmed MPV cases: 21,894 (9.9.2022). (full version). 
  • NY State: As of September 12 2022, a total of 3,552 confirmed orthopoxvirus/monkeypox cases – a designation established by the Centers for Disease Control and Prevention (CDC). (NY Sit Rep and County List)
  • Should Monkeypox Be Considered an STD? Experts Debate (WebMD) Monkeypox is almost always spread through skin-to-skin contact and, in the West, many of the cases have occurred among men who have sex with men. But health experts say that doesn’t make it an STD – at least not in “the classic sense.”

US Updates/News

  • Los Angeles health officials are investigating the death of a person who had monkeypox (CNBC) Dr. Rita Singhal, director of disease control in Los Angeles County, said it’s not clear what role monkeypox may have played in the person’s death. Officials do not have additional details at this time, Singhal said. “This is one of two deaths in the United States that are currently under investigation to determine whether monkeypox was a contributing cause of death,” Singhal told reporters during a press conference Thursday.

Global Updates/News

  • Monkeypox Shots, Treatments and Tests Are Unavailable in Much of the World (NY Times) The scramble for monkeypox vaccines and treatments has been centered in the United States and Europe, where supplies of shots have stretched thin or nearly run out. But more than 100 countries are now reporting monkeypox cases, and a vast majority of those have had no vaccine or treatments at all.
  • Downward monkeypox trends continue in Europe, Americas (CIDRAP) Today World Health Organization (WHO) Director-General Tedros Adhanom Ghebeyesus, PhD, said the monkeypox outbreak in Europe continues to decline, and there are some signs the outbreak in the Americas is on the same trajectory.
  • Monkeypox Virus Also Causes Neurological and Psychiatric Damage [New Study] (Nature World News)  [A] small portion of the human population between 2-3% infected with monkeypox develop serious neurological problems such as seizure and encephalitis. [A] few numbers of study participants showed sign of confusion in a cognitive level. A relatively broad group of people also exhibited common neurological symptoms like fatigue, headache, and muscle ache.

Official Guidance Sources

Articles by Category


Projecting the impact of testing and vaccination on the transmission dynamics of the 2022 monkeypox outbreak in the United States (Zheng et al., Journal of Travel Medicine)

Researchers constructed an epidemic dynamical model, which partitioned the total US population into seven epidemiological compartments based on the different status of disease diagnosis. This model considers heterogeneous (both close/sexual and general) contacts, associated with different secondary attack rates and different number of contacts exposed to an infected individual. The efficacy of currently available smallpox vaccines against monkeypox was estimated as 85% for both routine vaccination and ring vaccination. They retrospectively (prior to July 15th) simulated the MPXV epidemic dynamics across the most heavily affected states in the United States. Notable gaps were observed between estimated and confirmed numbers of cases in six representative states. The total number of infected cases is estimated as 1.8 (95% CI 1.3-3.4) times of the reported number. This suggests that a substantial proportion of infected cases were not diagnosed or reported during this period of the outbreak. At the early stage of the outbreak, the average time from disease onset to diagnostic confirmation and reporting required 9 days. Infected but unconfirmed cases exacerbated the spread of MPXV. If this reporting delay could be shortened to 5 or 3 days, the number of cumulative infections would be reduced by 96.9% and 99.4%, respectively, by the end of 2022. Notably, thousand infections could be prevented for the state of New York alone, by shortening the diagnosis delay from 5 to 3 days. The implementation of ring vaccination has a clear coverage-dependent effect on curbing the spread of MPXV. If the median delay from disease onset to confirmation were shortened to 5 days, but without ring vaccination, there would be 74169 cumulative infections in 2022 in the United States. Vaccinating 20% of exposed contacts would reduce cumulative cases by 32.3% by the third quarter and by 61.1% by the end of 2022. If vaccination coverage reached 40% and 60%, cumulative infections would be reduced by 78.3% and 81.8%, respectively, by the end of 2022. As a further demonstration of the robustness of their model, they found that the simulated cumulative infections from 15 July to 15 August, under the scenario of 30% vaccination coverage and 5 days between onset and conformation that is in line with the real-world situation, are well fitted to the reported data. This scenario, when compared to a 9-day delay between onset and conformation, would prevent 29.6% infections. In summary, this epidemic modelling study recapitulated the early transmission dynamics of the 2022 monkeypox outbreak in the United States.

HIV and Sexually Transmitted Infections Among Persons with Monkeypox — Eight U.S. Jurisdictions, May 17–July 22, 2022 (Curran et al., MMWR)

High prevalences of HIV and other sexually transmitted infections (STIs) have been reported in the current global monkeypox outbreak, which has affected primarily gay, bisexual, and other men who have sex with men (MSM). In previous monkeypox outbreaks in Nigeria, concurrent HIV infection was associated with poor monkeypox clinical outcomes. Monkeypox, HIV, and STI surveillance data from eight U.S. jurisdictions were matched and analyzed to examine HIV and STI diagnoses among persons with monkeypox and assess differences in monkeypox clinical features according to HIV infection status. Among 1,969 persons with monkeypox during May 17–July 22, 2022, HIV prevalence was 38%, and 41% had received a diagnosis of one or more other reportable STIs in the preceding year. Among persons with monkeypox and diagnosed HIV infection, 94% had received HIV care in the preceding year, and 82% had an HIV viral load of <200 copies/mL, indicating HIV viral suppression. Compared with persons without HIV infection, a higher proportion of persons with HIV infection were hospitalized (8% versus 3%). Persons with HIV infection or STIs are disproportionately represented among persons with monkeypox. It is important that public health officials leverage systems for delivering HIV and STI care and prevention to reduce monkeypox incidence in this population. Consideration should be given to prioritizing persons with HIV infection and STIs for vaccination against monkeypox. HIV and STI screening and other recommended preventive care should be routinely offered to persons evaluated for monkeypox, with linkage to HIV care or HIV preexposure prophylaxis (PrEP) as appropriate.

A large multi-country outbreak of monkeypox across 41 countries in the WHO European Region, 7 March to 23 August 2022 (Vaughan et al., Eurosurveillance)

In this report, authors describe the epidemiological features of monkeypox (MPX) and analyze disease severity as well as the effect of prior smallpox vaccination on all cases in the WHO European Region reported in The European Surveillance System (TESSy) up to 23 August 2022 to inform optimal public health responses. To assess the current epidemiological situation, they performed nowcasting on TESSy case-based data, with a prior negative binomial distribution (mean: 7 days and overdispersion 1.6 days) to adjust for reporting delay, and right truncation at 17 days, which corresponds to 95th percentile of reporting delay for cases in the last weeks. The median reporting delay, defined as the difference in days from date of symptom onset to date of notification at national level, was 7 days (range: 1–117 days) for 17,101 (82.6%) cases with complete date variables. Nowcast estimates suggest that the regional epidemic trend is plateauing overall, with some inter-country differences emerging. Most cases (98.8%; 17,685/17,896) identified as male, and the median age of all cases was 37 years and 37.2% (3,070/8,257) were HIV-positive. Among male cases, 96.9% (8,771/9,053) self-identified as men who have sex with men (MSM). A small proportion of infections have consistently been reported in women and children. Of those reporting symptoms, most reported rash (95.0%; 12,415/13,072) and at least one systemic symptom (64.8%; 8,476/13,072) such as fever, fatigue, muscle pain, chills or headache. The overall case hospitalization ratio was 10 per 1,000 cases and did not vary over time. Younger cases, those presenting with lymphadenopathy and those without systemic symptoms were at significantly higher risk of hospitalization (p = 0.015, p = 0.005 and p<0.001, respectively). Sexual contact was reported as a possible route of transmission in 93.9% (6,385/6,797) of cases, followed by other person-to-person routes (PTP; non-sexual, non-mother-to-child and non-healthcare associated, 5.3%; 359/6,797) or fomites (0.2%; 11/6,797). Lastly, only 16.8% (3,525/20,960) of cases reported on smallpox vaccination. Of these, most (81.8%; 2,577/3,152) self-reported as both unvaccinated prior to this outbreak and for this outbreak, 423 reported receiving a vaccination before this outbreak, one reported primary preventive (pre-exposure) vaccination (PPV) and 42 reported post-exposure preventative vaccination (PEPV) for this event.

Assessing transmission risks and control strategy for monkeypox as an emerging zoonosis in a metropolitan area (Yuan et al., Journal of Medical Virology)

In this modelling study, researchers aimed to model the spread of Monkeypox (MPX) in a metropolitan area for assessing the risk of possible outbreaks, and identifying essential public health measures to contain the virus spread. Using a One Health approach, the team modeled the spread of the MPX virus in humans considering potential animal hosts such as rodents (e.g., rats, mice, squirrels, chipmunks, etc.) and emphasize their role and transmission of the virus in a high-risk group, including gay and bisexual men-who-have-sex-with-men (gbMSM). From model and sensitivity analysis, they identified key public health factors and present scenarios under different transmission assumptions. In summary, modelling found that the MPX virus may spill over from gbMSM high-risk groups to broader populations if efficiency of transmission increases in the higher-risk group. However, the risk of outbreak can be greatly reduced if at least 65% of symptomatic cases can be isolated and their contacts traced and quarantined. In addition, infections in an animal reservoir will exacerbate MPX transmission risk in the human population. In summary, the authors conclude that regions or communities with a higher proportion of gbMSM individuals need greater public health attention. Tracing and quarantine (or “effective quarantine” by post-exposure vaccination) of contacts with MPX cases in high-risk groups would have a significant effect on controlling the spreading. Also, monitoring for animal infections would be prudent.

Monkeypox: disease epidemiology, host immunity and clinical interventions (Lum et al., Nature Reviews Immunology) 

Monkeypox virus (MPXV), which causes disease in humans, has for many years been restricted to the African continent, with only a handful of sporadic cases in other parts of the world. However, unprecedented outbreaks of monkeypox in non-endemic regions have recently taken the world by surprise. In less than 4 months, the number of detected MPXV infections has soared to more than 48,000 cases, recording a total of 13 deaths. In this Review, we discuss the clinical, epidemiological and immunological features of MPXV infections. We also highlight important research questions and new opportunities to tackle the ongoing monkeypox outbreak. 

Assessing Healthcare Workers’ Knowledge and Their Confidence in the Diagnosis and Management of Human Monkeypox: A Cross-Sectional Study in a Middle Eastern Country (Sallam et al., Infectious Disease Prevention and Public Health Promotion)

The ongoing multi-country human monkeypox (HMPX) outbreak was declared as a public health emergency of international concern. Considering the key role of healthcare workers (HCWs) in mitigating the HMPX outbreak, we aimed to assess their level of knowledge and their confidence in diagnosis and management of the disease, besides the assessment of their attitude towards emerging virus infections from a conspiracy point of view. An online survey was distributed among HCWs in Jordan, a Middle Eastern country, during May–July 2022 using a questionnaire published in a previous study among university students in health schools in Jordan. The study sample comprised 606 HCWs, with about two-thirds being either physicians (n = 204, 33.7%) or nurses (n = 190, 31.4%). Four out of the 11 HMPX knowledge items had <50% correct responses with only 33.3% of the study respondents having previous knowledge that vaccination is available to prevent HMPX. A majority of study respondents (n = 356, 58.7%) strongly agreed, agreed or somewhat agreed that the spread of HMPX is related to a role of male homosexuals. Confidence in the ability of diagnosis based on the available monkeypox virus diagnostic tests was reported by 50.2% of the respondents, while the confidence levels were lower for the ability to manage (38.9%) and to diagnose (38.0%) HMPX cases based on their current level of knowledge and skills. Higher confidence levels for HMPX diagnosis and management were found among physicians compared to nurses. The endorsement of conspiracy beliefs about virus emergence was associated with lower HMPX knowledge, the belief in the role of male homosexuals in HMPX spread, and with lower diagnosis and management confidence levels. The current study highlighted the gaps in knowledge regarding HMPX among HCWs in Jordan as well as the lack of confidence to diagnose and manage cases among physicians and nurses. Raising the awareness about the disease is needed urgently considering the rapid escalation in the number of cases worldwide with reported cases in the Middle East. The attitude towards male homosexuals’ role in HMPX spread necessitates proper intervention measures to prevent stigma and discrimination among this risk group. The adoption of conspiratorial beliefs regarding virus emergence was widely prevalent and this issue needs to be addressed with proper and accurate knowledge considering its potential harmful impact.


A brief on new waves of monkeypox and vaccines and antiviral drugs for monkeypox (Hung et al., Journal of Microbiology, Immunology and Infection) 

Monkeypox virus (MPXV), genetic closely linked to the notorious variola 3 (smallpox) virus, currently causes several clusters and outbreaks in the areas 4 outside Africa and is noted to be phylogenetically related to the West African 5 clade. To prepare for the upsurge of the cases of monkeypox in the Europe and 6 North America, two vaccines, Jynneos® in the U.S. (Imvamune® in Canada or 7 Imvanex® in the Europe) and ACAM2000® (Acambis, Inc.) initially developed 8 in the smallpox eradication program, can provide protective immunity to 9 monkeypox, and their production and availability are rapidly scaled up in the 10 response to the emerging threat. So far, these two vaccines are recommended 11 for people at a high risk for monkeypox, instead of universal vaccination. 12 Tecovirimat, an inhibitor of extracellular virus formation, and brincidofovir, a lipid 13 conjugate of cidofovir, both are in vitro and in vivo active against MPXV, and 14 are suggested for immunocompromised persons, who are at risk to develop 15 severe diseases. However, current general consensus in the response to the 16 monkeypox outbreak among public health systems is early identification and 17 isolation of infected patients to prevent its spread.


Clinical Use of Tecovirimat (Tpoxx) for Treatment of Monkeypox Under an Investigational New Drug Protocol — United States, May–August 2022 (O’Laughlin et al., CDC MMWR)

Currently, no Food and Drug Administration (FDA)–approved treatments for human monkeypox are available. Tecovirimat (Tpoxx), however, is an antiviral drug that has demonstrated efficacy in animal studies and is FDA-approved for treating smallpox. Use of tecovirimat for treatment of monkeypox in the United States is permitted only through an FDA-regulated Expanded Access Investigational New Drug (EA-IND) mechanism. CDC holds a nonresearch EA-IND protocol that facilitates access to and use of tecovirimat for treatment of monkeypox. The protocol includes patient treatment and adverse event reporting forms to monitor safety and ensure intended clinical use in accordance with FDA EA-IND requirements. To describe characteristics of persons treated with tecovirimat for Monkeypox virus infection, demographic and clinical data abstracted from available tecovirimat EA-IND treatment forms were analyzed. As of August 20, 2022, intake and outcome forms were available for 549 and 369 patients, respectively; 97.7% of patients were men, with a median age of 36.5 years. Among patients with available data, 38.8% were reported to be non-Hispanic White (White) persons, 99.8% were prescribed oral tecovirimat, and 93.1% were not hospitalized. Approximately one-half of patients with Monkeypox virus infection who received tecovirimat were living with HIV infection. The median interval from initiation of tecovirimat to subjective improvement was 3 days and did not differ by HIV infection status. Adverse events were reported in 3.5% of patients; all but one adverse event were nonserious. Authors conclude that these data support the continued access to and treatment with tecovirimat for patients with or at risk for severe disease in the ongoing monkeypox outbreak.


Clinical characteristics and comparison of longitudinal qPCR results from different specimen types in a cohort of ambulatory and hospitalized patients infected with monkeypox virus. (Nörz et al., Journal of Clinical Virology)

The aim of this study was to compare clinical data with longitudinal qPCR results from lesion swabs, oropharyngeal swabs and blood in a well characterized patient cohort. 16 patients (5 hospitalized, 11 outpatients) were included in the study cohort and serial testing for monkeypox virus-DNA carried out in various materials throughout the course of disease. Laboratory analysis included quantitative PCR, next-generation sequencing, immunofluorescence tests and virus isolation in cell culture. All patients were male, between age 20 and 60, and self-identified as men having sex with men. Two had a known HIV infection, coinciding with an increased number of lesions and viral DNA detectable in blood. In initial- and serial testing, lesion swabs yielded viral DNA-loads at, or above 106 cp/ml and only declined during the third week. Oropharyngeal swabs featured lower viral loads and returned repeatedly negative in some cases. Viral culture was successful only from lesion swabs but not from oropharyngeal swabs or plasma. The data presented underscore the reliability of lesion swabs for monkeypox virus-detection, even in later stages of the disease. Oropharyngeal swabs and blood samples alone carry the risk of false negative results, but may hold value in pre-/asymptomatic cases or viral load monitoring, respectively.

The resurgence of a neglected orthopoxvirus: Immunologic and clinical aspects of monkeypox virus infections over the past six decades (Al-Musa et al., Clinical Immunology)

Monkeypox is a zoonotic Orthopoxvirus which has predominantly affected humans living in western and central Africa since the 1970s. Type I and II interferon signaling, NK cell function, and serologic immunity are critical for host immunity against monkeypox. Monkeypox can evade host viral recognition and block interferon signaling, leading to overall case fatality rates of up to 11%. The incidence of monkeypox has increased since cessation of smallpox vaccination. In 2022, a global outbreak emerged, predominantly affecting males, with exclusive human-to-human transmission and more phenotypic variability than earlier outbreaks. Available vaccines are safe and effective tools for prevention of severe disease, but supply is limited. Now considered a public health emergency, more studies are needed to better characterize at-risk populations and to develop new anti-viral therapies.