WHO introduces Go.Data and the Early Warning and Alert Response System (EWARS) as the main system for COVID-19 surveillance. The Go.Data program is an outbreak investigation tool designed to collect data during health emergencies. Go.Data is then implemented in the DKI Jakarta surveillance system [17]. Meanwhile, EWARS is a system designed to increase the capability of detecting outbreaks in an emergency. On 23 April 2020, WHO socialized EWARS to representatives of the Directorate of Health Surveillance and Quarantine, Ministry of Health (MoH) of the Republic of Indonesia, and regional surveillance officers. WHO together with representatives from Indonesia also agreed on the consistent use of EWARS and conducted weekly meetings to discuss surveillance challenges in the field [18].

WHO supports surveillance activities on Halodoc, GOJEK, and Tokopedia. The three online applications provide screening and health consultation regarding COVID-19 symptoms. Users of the three applications who have symptoms of COVID-19 will be directed to take the COVID-19 test and get further treatment [19].

The Global Influenza Surveillance and Response System (GISRS) is usually used to monitor cases of Influenza-Like Illness (ILI) and Severe Acute Respiratory Infections (SARI). By using GISRS, the tracking of COVID-19 cases will be even tighter. Suspected cases with mild symptoms, which are often not identified through the COVID-19 surveillance system, will still be identified through the ILI and SARI surveillance sentinels [20]. To strengthen the use of GISRS in Indonesia, WHO held refresher training for Influenza surveillance sentinel officers. The refresher training is divided into two sessions. The first session was conducted on 25-26 June 2020 and was attended by 133 officers from 26 ILI surveillance sentinels. Meanwhile, the second refresher training session was held on 29-30 June 2020 and was attended by 35 officers from 6 SARI surveillance sentinels [21].

In Indonesia, there is a homecoming tradition, where Indonesian people go back to their hometown to celebrate Eid al-Fitr with their families. With this tradition, there will be high mobilization than can lead to an increasing number of COVID-19 cases. Therefore, WHO assisted the Indonesian Government to anticipate the rising number of COVID-19 cases due to this tradition. WHO coordinated with the International Federation of Red Cross and Red Crescent Societies (IFRC) to activate Community Based Surveillance (CBS). Thereafter, the public can participate directly in the process of tracking the Coronavirus and the local Local Health Center (Puskesmas) can conduct COVID-19 testing for travelers [22].

WHO encouraged MoH to carry out field investigations by disseminating tracking officers throughout the Indonesian territory. With the assistance of the Food Agriculture Organization (FAO), WHO, and MoH succeeded in compiling and publishing a guidebook for contact tracing officers at the provincial level [23]. On July 6, 2020, WHO, FAO, and the Indonesian MoH also agreed to establish a Contact Tracing Center at the national and regional levels. This establishment is expected to improve and simplify the supervision of contact tracing [24].

WHO, FAO, and MoH collaborated to develop an application to trace close contacts, called “Silacak”. The quality of this application continues to be improved. Recently, Silacak is already available in the mobile version and it has features to analyze data and monitor the daily COVID-19 reports from various Puskesmas. The purpose of developing the Silacak application is to make tracking officers easily trace close contacts at the provincial or district level, monitor close contact's activities, and analyze, and report data [25].

The contribution of WHO to strengthen Indonesia's COVID-19 surveillance was also seen in the refresher training and evaluation meetings for contact tracing officers. The refresher training was held online on 10-11 September 2020 and attended by at least 700 contact tracing officers from 514 regions of Indonesia [26]. Then, it was continued by facilitating refresher training for 300 contact tracing officers from 51 cities in 10 priority provinces: Aceh, Bali, Central Java, DKI Jakarta, East Java, North Sumatra, South Sumatra, South Kalimantan, Papua, and West Java on 3rd November 2020 [27].

The development of contact tracing in ten priority provinces was then evaluated in a meeting conducted on November 21-22 2020. This evaluation meeting became a forum for field officers from various regions of Indonesia to exchange information, experiences, and challenges encountered during the contact tracing process [28]. In addition to facilitating training for regional contact tracing officers, WHO were also paying attention to tracking COVID-19 cases at the country's Point of Entry (POE). Because COVID-19 is an imported case, the country's PEO can be the initial location for the transmission of the Coronavirus. If the COVID-19 surveillance system at the POE is weak, the virus will spread widely in the territory of Indonesia. To anticipate the worst scenario at the country's entrance, since March 2020, WHO has supported the implementation of training on contact tracing for 80 field officers and health workers at ports [19].

WHO has assisted Indonesia in providing COVID-19 testing tools and materials, such as testing kits, reagents, PCR equipment, extraction tools, Viral Transport Medium (VTM), and others. Starting from Quarter-I of 2020, WHO sent 150 reagents with a capacity of 15,000 reactions for screening and 45 reagents with a capacity of 4,500 reactions for COVID-19 confirmation tests to the Indonesia National Health Research and Development Agency (Balitbangkes) [17]. Then, in Quarter-II of 2020, WHO distributed 1,000 VTMs to the Directorate of Health Surveillance and Quarantine of the Indonesian MoH [22]. This was followed by the submission of 40,000 primers and probes for screening; 12,000 primers and probes for COVID-19 confirmatory testing; 20 PCR kits with a testing capacity of up to 108,900 people; 128 nucleic acids and extraction apparatus for sample preparation; and 3 sets of centrifuges to process the extraction with reagents, to Balitbangkes [29]. In the third quarter of 2020, WHO provided 253,800 VTM and swab kits, which is equivalent to US$ 532 thousand, to the Directorate of Health Surveillance and Quarantine of the Indonesian MoH. The laboratory equipment was then distributed to 34 provinces of Indonesia [30]. In addition, WHO also provided 140 antibody test kits and Enzyme-Linked Immunosorbent Assay (ELISA), worth US$ 80 thousand, which will be used for seroepidemiological research at Balitbangkes and selected laboratories [31]. In September 2020, WHO provided 140 sets of reagents that can be used for 13,440 COVID-19 tests in Indonesia.

WHO also contributes to the expansion of the national COVID-19 laboratory network, namely by facilitating training for laboratory staff and formulating guidelines for PCR procedures. WHO is aware that expanding the laboratory network does not only require adequate tools and materials but also requires qualified human resources who are familiar with the COVID-19 screening mechanism. In April 2020, for the first time, WHO together with Balitbangkes held training for 18 experts from 9 regional laboratories related to the use of Real-Time Polymerase Chain Reaction (RT-PCR). Representatives from the WHO Collaborating Center for Infectious Diseases Reference Laboratory in Australia also attended the training and presented the procedure for detecting SARS-CoV-2 in specimens [16].

WHO and Balitbangkes continue to socialize the procedures of using PCR as a COVID-19 diagnostic tool through several webinars. As in the webinar held on April 24, 2020, WHO and Balitbangkes explained risk management in handling the Coronavirus and procedures for using PCR tests in front of 135 participants from the Food and Drug Supervisory Agency (BPOM). The next day, WHO and Balitbangkes again held a webinar about the character and pathogens of the Coronavirus. In the webinar which was attended by 181 participants, WHO together with Balitbangkes also presented the importance of applying biosafety and biosecurity in COVID-19 laboratories [19].

In the same month, WHO, Balitbangkes, US Centers for Disease Control and Prevention (US CDC), and the Association of Public Health Laboratories (APHL) held a meeting to prepare two PCR training sessions for experts from 100 laboratories, which will be held on 28 April-2 May 2020 and 5-9 May 2020. This training will cover the discussion of procedures for specimen collection, testing, recording, interpretation of results, components of biosafety, and biosecurity [32], to fill the examination capacity gap and speed up test results, WHO introduced the use of PCR tools of the Abbott m2000 and Cepheid GeneXpert® types to the TB Sub-Directorate, HIV Sub-Directorate, and Emerging Infectious Diseases Sub-Directorate of the Indonesian Ministry of Health [18].

In May 2020, there were two online PCR training sessions conducted by WHO and Balitbangkes. This PCR training was attended by 366 participants from 52 Indonesian laboratories who met the qualifications for conducting PCR. WHO presented the latest laboratory examination guidelines, distributed laboratory capacity assessment tools, and identified problems or challenges encountered during the Corona assessment process. As of May 6, 2020, there were already 711 laboratory experts trained to use PCR [33]. The PCR examination training facilitated by WHO would continue until mid-2020. On 15-19 June 2020, WHO participated in two PCR training sessions organized by the Indonesian Ministry of Health, the Center for Health Human Resources Development and Empowerment (PPSDM), and APHL. In front of 200 training participants, WHO explained the development of COVID-19 cases and guidelines for identifying the new type of Coronavirus [21] Training for Indonesian laboratory experts is not limited to a national scope. WHO Country Office Indonesia always informed and invited Indonesian laboratory staff to participate in training about COVID-19 testing organized by the WHO South East-Asia Region (SEARO) or other regions.

The purpose of conducting various laboratory training is that the COVID-19 test in Indonesia has the same standards as WHO interim guidance. This was delivered by a spokesperson of the COVID-19 Laboratory of the Medical Faculty of Islamic State University Syarif Hidayatullah Jakarta, dr. Erike Anggraini explained that WHO encourages laboratories in Indonesia to comply with the principles of “True Positive” and “True Negative”. National laboratories have to deliver the results of the COVID-19 testing honestly and transparently. If there is an indication of SARS-CoV-2 in a specimen, the laboratory has to report the specimen as a positive case. Vice versa, if there is no indication of SARS-CoV-2 in a specimen, the laboratory has to categorize the specimen as a negative case [34].

Regarding the design of national diagnostic guidelines, WHO has participated in making video tutorials of PCR mechanisms for COVID-19 tests with the Tuberculosis Sub-Directorate of the Indonesian MoH and the Department of Microbiology, University of Indonesia. On the video-making process, WHO provided input regarding sampling, examination, and reporting of COVID-19.22 In September, WHO, Balitbangkes, US CDC, APHL, and the PPSDM Agency agreed to design a guide for PCR equipment which will be the main guidelines for laboratory staff on detecting Coronavirus. In the next meeting which was held on October 9, 2020, WHO and partners began to finish out the PCR guidelines [35]. WHO Country Office in Indonesia actively informs the laboratory diagnostic guidelines that have been updated to national laboratory officers. Shortly after the emergence of a new variant of COVID-19, WHO Indonesia immediately translated and distributed guidelines for detecting the new variant of COVID-19 to all reference laboratories [34].

The role of WHO in expanding the COVID-19 laboratory network is also carried out by using laboratories under Influenza sentinel surveillance. WHO recommends testing samples from the ILI and SARI laboratories twice. The purpose of testing the samples twice is to confirm the indication of Influenza and COVID-19. The use of the Influenza laboratory is aligned with the WHO surveillance strategy in Indonesia, which is related to the activation of GISRS [36].

The role of WHO in the national diagnostic laboratory is not limited to facilitating training and designing guidelines for Coronavirus tests. However, WHO observes the national laboratories directly to ensure the quality of the COVID-19 laboratory in Indonesia. Quality assurance is measured by conducting a proficiency test, whereas WHO sends an examination panel containing specimens that must be tested and answered by the laboratory staff. After examining the samples, the relevant laboratory staff needs to report which specimens are positive and which are negative in an application provided by WHO. If all the answers submitted are correct, the relevant laboratory will get a certificate of passing the proficiency test, 170 COVID-19 laboratories have passed the WHO proficiency test, and if they have not passed, they will be trained again [34].