critically appraise the article, Yellow Fever Outbreak in Darfur, Sudan in October 2012; the Initial Outbreak Investigation Report using the steps of outbreak report

criticize the paper Summary Introduction: Sudan is subject to repeated outbreaks, including Viral Hemorrhagic Fever (VHF), is considered to be a very serious illness. Yellow Fever (YF) outbreaks in Sudan have been reported from the 1940s through 2005. In 2012, a new outbreak of YF occurred in the Darfur region. Objective: To identify the potential for an outbreak, to diagnose the disease, and to be able to recognize its cause among the initial reported cases. Methodology: >This is a descriptive and investigative field study that applies standard communicable disease outbreak investigation steps. The study involved clinical, serological, entomological and environmental surveys. Results: The field investigation confirmed the outbreak and identified its cause to be YF. Conclusion: National surveillance systems should be strong enough to detect VHFs in a timely manner. Local health facilities should be prepared to promptly treat the initial cases because the case fatality ratios (CFRs) are usually very high among the index cases.

criticize Steps of the outbreak investigation Preparation to investigate Immediately after the construction of the investigation team, the team conducted a brief meeting and distributed the responsibilities and the field tasks between them. The head of the investigation team opened the contact channels with the Central and South Darfur states and shared the main objectives of the mission. The head of the team also secured the required field tools and commitments. The team members conducted a thorough literature review of the basic concepts of hemorrhagic fevers, their epidemiology, transmission and ways to investigate the outbreak. The team revised all records of similar problems reported to the FMOH during the last several years, particularly from areas with similar geography and demographics. Verification of the diagnosis and confirmation of the outbreak Because the serum samples that the National Public Health Laboratory (NPHL) received were not tested until the departure of the team, the team revised the symptomatology and clinical presentations of the reported cases from the clinic registers (Nertiti rural hospital and Nyala). We have interviewed the health care providers who attended the reported patients (medical assistants, nurses and medical doctors) in each hospital. According to the documented descriptions, the investigation team suggested the following deferential diagnoses: • Crimean Congo Hemorrhagic Fever CCHF; • Rift Valley Fever RVF; • Yellow Fever YF; • Complicated Malaria; • Dengue, Zika virus infection and other VHFs; • Viral Hepatitis disease, particularly Hepatitis A (HAV), Hepatitis B (HBV), Hepatitis C (HCV) and Hepatitis E (HEV). We ranked these differential diagnoses because the majority of cases were reporting fever and bleeding. In addition, the area had just experienced a very heavy rainy season. Most of the community members are farmers and animal pastoralists and have close, direct contact with their animals. Due to the fact that few patients were reporting jaundice, we ranked CCHF and RVF first. We ranked YF third because few patients had reported jaundice. However, we considered the sylvatic cycle of YF transmission because the area that had reported the index cases is very close to the jungle. Wild monkeys inhabit the jungle, and people usually go there with their animals for rearing. The team conducted field entomological studies, collected additional blood samples and shipped them to the NPHL in Khartoum for confirmation and demarcating out between the possible diagnoses. Case definition When the team reached the field, we made a very broad case definition as a method to include as many diseased cases as possible for blood sample collection for testing and confirmation. Our field case definition was any patient who developed a sudden high-grade fever ≥38 ◦C with or without bleeding, jaundice, vomiting or prostration after October 1. We used this case definition to guide our hospital visits, to facilitat

criticize Methodology Design This was a descriptive field investigation study that applied the standard communicable disease outbreak investigation steps [11]. In this study, epidemiological description, ecological, entomological and serological surveys were conducted. Study area The study area consisted of the two Darfur states, Central and South Darfur, in the western part of Sudan. The total populations for the two states are 1,022,740 and 3,485,815, respectively [12]. The area is currently suffering from the complications of civil war and longstanding conflicts. Study population The study population consisted of patients who were diagnosed with hemorrhagic fever and had been reported to the national directorate of epidemiology and zoonotic disease within the Federal Ministry of Health of the Republic of the Sudan through the national communicable disease surveillance system. Other people who were epidemiologically linked to these reported cases, in addition to domestic animals and insects that were present at the areas from which cases were reported, were also included in the study population. Study timing The study was conducted from October 2—20, 2012. During this time period, all standard operational steps of communicable disease outbreak investigation were performed, including preparation, field investigations and laboratory confirmation of the organism responsible for the outbreak. Context background On October 1, 2012, the national surveillance system of the Directorate of Epidemiology and Zoonotic disease with the Federal Ministry of Health of the Sudan reported 7 cases with suspected Viral Hemorrhagic Fever (VHF). These cases were from the Khour Ramla village of the Nertiti locality, which belongs to the newly formed Central Darfur state. These cases presented with sudden onset fever, body aches, vomiting and bleeding manifestations. Some cases also presented with jaundice. Five of these cases died, with a CFR of 71.4%. Some of these patients were referred from Nertiti rural hospital to Nyala hospital in the capital city of South Darfur state (the detailed case description will be provided below). The National Directorate of Epidemiology and Zoonotic disease conducted its systematic discussions and reviews. An investigation team was immediately sent to assess the situation in the field, to explore the potential for an outbreak and to find the possible causes and sources of the event. The team consisted of an epidemiologist, an entomologist, public health surveillance officers and a laboratory technician from FMOH. The team arrived in the field by October 10 through the 372 M.A. Soghaier et al. United Nations Humanitarian Air Service (UNHAS), which was facilitated by the World Health Organization (WHO) & WFP country offices.

4. Case Studies and Examples: 4.1 The Australian Biosecurity System: 4.2 The Ebola Outbreak in West Africa:

criticize Verification of the diagnosis and confirmation of the outbreak Because the serum samples that the National Public Health Laboratory (NPHL) received were not tested until the departure of the team, the team revised the symptomatology and clinical presentations of the reported cases from the clinic registers (Nertiti rural hospital and Nyala). We have interviewed the health care providers who attended the reported patients (medical assistants, nurses and medical doctors) in each hospital. According to the documented descriptions, the investigation team suggested the following deferential diagnoses: • Crimean Congo Hemorrhagic Fever CCHF; • Rift Valley Fever RVF; • Yellow Fever YF; • Complicated Malaria; • Dengue, Zika virus infection and other VHFs; • Viral Hepatitis disease, particularly Hepatitis A (HAV), Hepatitis B (HBV), Hepatitis C (HCV) and Hepatitis E (HEV). We ranked these differential diagnoses because the majority of cases were reporting fever and bleeding. In addition, the area had just experienced a very heavy rainy season. Most of the community members are farmers and animal pastoralists and have close, direct contact with their animals. Due to the fact that few patients were reporting jaundice, we ranked CCHF and RVF first. We ranked YF third because few patients had reported jaundice. However, we considered the sylvatic cycle of YF transmission because the area that had reported the index cases is very close to the jungle. Wild monkeys inhabit the jungle, and people usually go there with their animals for rearing. The team conducted field entomological studies, collected additional blood samples and shipped them to the NPHL in Khartoum for confirmation and demarcating out between the possible diagnoses.