Peru: MOH Declares Health Emergency Over Increase In Guillain-Barré Syndrome

[Michael Coston]

Peru: MOH Declares Health Emergency Over Increase In Guillain-Barré Syndrome


Photo Credit - MINSA


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Two days ago Peru's Ministry of Health declared a 90-day Health Emergency due to a sharp rise in the number of Guillain-Barre syndrome (GBS) reported across the country. Readers with long memories may recall we saw a similar declaration in June of 2019, which was eventually linked to a Campylobacter outbreak.

While many people erroneously assume vaccines are the primary cause of GBS, it is most often associated with bacterial or viral infections. The CDC describes the disorder:

What is Guillain-Barré syndrome (GBS)?

Guillain-Barré syndrome (GBS) is a rare disorder in which a person’s own immune system damages their nerve cells, causing muscle weakness and sometimes paralysis. GBS can cause symptoms that usually last for a few weeks. Most people recover fully from GBS, but some people have long-term nerve damage. In very rare cases, people have died of GBS, usually from difficulty breathing. In the United States, an estimated 3,000 to 6,000 people develop GBS each year.

What causes GBS?

The exact cause of GBS is unknown, but about two-thirds of people who develop GBS experience symptoms several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacteriumCampylobacter jejuni is one of the most common risk factors for GBS. People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

Clusters of GBS are rare, but we have seen them reported (see 2011's The Sonora/Arizona GBS Cluster). In that particular case, the outbreak was linked to inadequately disinfected tap water (see Binational outbreak of Guillain-Barré syndrome associated with Campylobacter jejuni infection, Mexico and USA, 2011.)

The (translated) press release from Peru's MOH follows. I'll have more after the break.

Government declares health emergency due to unusual increase in cases of Guillain Barré syndrome

Press release

- Head of Minsa reported that the measure seeks to protect the health and life of the population - More than S/ 12 million is allocated for the purchase of immunoglobulin and other supplies

July 8, 2023 - 3:45 p.m.

Due to the unusual increase in cases of Guillain Barré syndrome (GBS), the Government, through Supreme Decree No. 019-2023-SA, declared a national health emergency for a period of 90 calendar days, reported the minister of Health, César Vásquez, during his visit to the National Institute of Neurological Sciences (INCN) where he visited two patients hospitalized for this disease.

“So far we have controlled the disease. Guillain Barré appears every year and there has been a significant increase in recent weeks that forces us to take actions as a State to protect the health and life of the population, "said the head of the Ministry of Health (Minsa ) .

The minister explained that this declaration, approved yesterday by the Council of Ministers, will allow the purchase, through the National Center for the Supply of Strategic Health Resources (Cenares), immunoglobulin for the treatment of GBS patients for up to the next two years.

The decree contemplates the action plan that includes financing for the acquisition of goods and services for an amount greater than S/ 12 million. The minister recalled that plasmapheresis and immunoglobulin treatments are available in hospitals and institutes located in the regions of Piura, Cajamarca, La Libertad, Puno, Huánuco, Callao, Loreto, Áncash and Lima.

“The regions are supplied with medicines, and for those that need we have started a redistribution while buying. As Minsa we are assuming the leadership that corresponds to us. We are sitting down with the regional authorities to see their budget execution, because the patients must have their proper treatment”, affirmed the minister.

To date, a total of 182 GBS cases have been reported. Of these, 31 patients are hospitalized and 147 have been discharged. Unfortunately, 4 deaths occurred in January, March and May.

NATIONAL INSTITUTE OF NEUROLOGICAL SCIENCES

This morning, the Minister of Health went to the National Institute of Neurological Sciences (INCN), in order to verify the care provided to two patients with SGC, as well as to the other hospitalized in this establishment.

The minister was received by the director of the INCN, Jorge Medina Rubio, with whom he toured all areas, such as hospitalization, outpatient, emergency, pharmacy, Intermediate Care Unit (NICU), as well as the Museum of Neuropathology.

The authority spoke with the relatives of the patients and guaranteed them timely and quality care. Likewise, it collected the demands of health workers related to medicine, equipment and human resources.

In addition to the 2019 outbreak previously mentioned, Peru saw an outbreak in 2018 which was tentatively linked to an enterovirus outbreak (see Outbreak of Guillain-Barre syndrome in Peru), and earlier outbreaks have been loosely tied to Zika infections.

A 2022 review (see below) published in the Journal of the Faculty of Human Medicine offers a long list of potential viral causes of GBS (including Zika, EV-D68, Influenza A & B, Dengue, SARS-COV-2, etc.), and is well worth reading in its entirety.

Viral etiology of the Guillain-Barré syndrome: Looking for the idiopathic answer

Jorge Arturo Vega Fernández1 , Biologist - Microbiologist
Danny Omar Suclupe Campos1 , Biologist - Microbiologist
Mayra Massely Coico Vega1 , Biologist - Microbiologist
Franklin Rómulo Aguilar Gamboa2 , Biologist - Microbiologist

1Department of Microbiology, Faculty of Biological Sciences, Pedro Ruiz Gallo University. Lambayeque, Peru.
2Immunology-Virology Laboratory, Lambayeque Regional Hospital. Lambayeque, Peru.

ABSTRACT

Guillain-Barré Syndrome (GBS) is a rare disorder of the nervous system, where the patient's immune system attacks the peripheral nerve cells in the arms and legs, causing muscle weakness, loss of sensation and sometimes total paralysis. The origin of this disorder has been associated with immune responses triggered by post-infection with Campylobacter spp.
However, when there is no obvious cause of the disease, it is usually not investigated due to the greater interest in the treatment. Therefore, most cases are reported as idiopathic origin.

Between January and March 2016 worldwide, GBS outbreaks were reported in 8 countries, linked to the emergence of the Zika virus. In Peru, GBS outbreaks have been reported more frequently since the end of 2018 and, although no association with Zika has been confirmed, the increase in cases, the geographical extension where they occurred and the clinical characteristics of affected patients, have common patterns that lead to suspect an infectious origin mainly of viral type.

Therefore, it is important to know the current scientific evidence about the role that some viruses play in this syndrome, allowing us to expand our epidemiological picture with new tools to deal with this disease.

(Continue . . . )


While we await further word on the size, scope, and etiology of Peru's latest Guillain-Barré outbreak, a few past blogs on GBS may be of interest.

Nature: Long-term Neurologic Outcomes of COVID-19

Nature Study: Greater Risk Of Neurological Complications From COVID Infection Than From Vaccine

Remembering An Emergency Pandemic Vaccine Program That Went Awry

NEJM: Guillain–Barré Syndrome Associated with Zika Infection - Colombia

WHO Risk Assessment On Guillain-Barré Syndrome & The Zika Virus

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https://afludiary.blogspot.com/2023/07/peru-moh-declares-health-emergency-over.html

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Translation Google

What we know about the Guillain-Barré syndrome epidemic in Peru

The South American country has been under scrutiny by public health specialists since the increase in reported cases and the death of four patients in early July. A state of emergency has been declared, but the cause is still unknown.

By Noé Amsallem and William Audureau
Posted today at 3:08 p.m., edited at 3:29 p.m.

What is Guillain-Barré syndrome?

Guillain-Barré syndrome (GBS) is most often a rare post-infectious disease in which the immune system attacks the peripheral nervous system, the one that circulates information between the brain and the organs.

It is characterized, at first, by unusual sensations (tingling, tingling, feeling of cold) or the absence of sensitivity, as well as a feeling of weakness, fatigue and muscle cramps at rest, recalls the High Authority of health (HAS). The disease develops rapidly and its symptoms worsen within a few days, which can lead to paralysis of the limbs, damage to the chest muscles, and even the ability to speak and swallow.

In most cases, patients recover without sequelae within a few weeks. But, "even in the best health contexts, 3% to 5% of patients die from complications of the disease, such as paralysis of the muscles of respiration, sepsis, pulmonary embolism or cardiac arrest", summarizes the World Health Organization (WHO) .

According to a 2021 report from the rare neuromuscular diseases sector (Filnemus), one of the twenty-three French national coordination structures for rare disease actors, its incidence rate increases with age, ranging from 0.6 per 100 000 per year in children to 2.7 per 100,000 per year in people aged 80 and over.

Why is the situation in Peru worrying?

On June 23, Peruvian health authorities issued an alert due to an abnormally high number of GBS cases. As of July 9, 191 cases have been detected since the start of the year, and four patients have died. However, this pathology requires very heavy care, “with 20% to 30% of admissions to intensive care” , specifies Mahmoud Zureik, professor of epidemiology and public health at the University of Versailles-Saint-Quentin-en -Yvelines. In 2022, the total number of intensive care beds was estimated at 1,200 by the Peruvian newspaper La Republica. "There is a fear of saturation of services ," confirms Nicolas Weiss, neurologist at the Pitié-Salpétrière hospital in Paris.

On Sunday July 9, the Peruvian Ministry of Health declared “a national level health emergency (…) for ninety days” . A decision that can be as health as political. “One of the reasons is also the fact that the Ministry of Health says that they don't have enough treatment for GBS , specifies Mr. Weiss . Triggering the state of health emergency could allow them to access care or unlock WHO aid. The Peruvian health authorities have not communicated since .

What could be the causes of the epidemic?

Very often, this inflammatory disease is a reaction to an infection. "In two-thirds of cases, the occurrence of Guillain-Barré syndrome is preceded within three weeks to one month by an acute viral or bacterial infectious episode, in particular infections of the respiratory or digestive tracts", specified the French Agency for safety of health products (Afssaps) in a 2009 report . But the precise cause may remain unknown. "Sometimes we don't know because we haven't done the major studies, which are quite expensive, with large control groups" , regrets Professor Weiss.

Certain diseases are known to trigger it. Thus Covid-19, as a review of scientific literature from 2023 showed. Hospitalization for severe Covid even multiplies by eight the risks of developing GBS in the event of severe Covid. But this phenomenon has remained "very marginal" , nuances the neurologist.

Other diseases can be the cause. French researchers thus showed in 2016 the causal link between infection with the Zika virus, characterized by flu-like symptoms, and the onset of GBS. They had observed an increase in hospitalizations due to this disease at the time of the Zika virus epidemic in French Polynesia, in 2013-2014.

In the case of Peru, dengue appears as an ideal suspect. The country has been facing its most serious epidemic since June since 1990. A situation caused by the passage in the spring of Cyclone Yaku, whose torrential rains attracted the tiger mosquito, the main vector of the disease. "In time, it could fit perfectly ," agrees Professor Zureik. But not everything fits. The epidemiologist notes the surprising geographical extent of current cases of GBS, while dengue is localized in the south of the country.

Other avenues are being considered. In 2019, the Latin American country had already been hit by a historic GBS epidemic. This had been caused by a meat-borne bacteria, Campylobacter jejuni , a 2021 retrospective study found . But between these different hypotheses, the incomplete communication of the Peruvian health authorities does not make it possible to decide, regrets Mahmoud Zureik. Dengue, Zika, unidentified viruses or bacteria… at this stage, he repeats, “we don't know”. The only certainty: the cause can only be recent, within a maximum of six weeks before the onset of GBS.

Why do some people blame the Covid-19 vaccines?

Since the large-scale vaccination campaigns against Covid-19, anti-vaccine circles have seen every medical event as a side effect of injections. The Peruvian situation is no exception, the most active figures in this movement, who have been predicting the worst for two years, have established a link between this peak of GBS in Peru and vaccination in the country.

Guillain-Barré syndrome is a rare side effect of vaccines, especially those against the flu . Regarding those against Covid-19, the European Pharmacovigilance Risk Assessment Committee (PRAC) recognized , in September 2022, a link with the AstraZeneca vaccine. However, it remains very rare since it affects less than one person in 10,000, recalls the European Medicines Agency. A 2021 British study estimates that a "probable" link could be established for fifty-six cases of GBS out of more than 85 million vaccinations .

In the case of Pfizer's vaccine, cases of GBS have been under observation by the National Agency for the Safety of Medicines since August 2021 , but no link has ever been formally established, and recent scientific literature is rather reassuring. Finally, vaccination with AstraZeneca has only been marginal in Peru, and dates from two years ago: difficult to see there the cause of an inflammatory reaction in 2023.

https://www.lemonde.fr/les-decodeurs/article/2023/07/14/ce-que-l-on-sait-de-l-epidemie-de-syndrome-de-guillain-barre-au-perou_6181981_4355770.html

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Concerning the 2023 dengue outbreak in Peru, please see:

https://flutrackers.com/forum/forum/emerging-diseases-other-health-threats-alphabetical-a-thru-h/dengue/968831-peru-2023-dengue

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Translation Google

CDC Peru and PAHO/WHO hold a virtual session to share information on the epidemiological situation of Guillain-Barré Syndrome in Peru

Lima, July 14, 2023.

The National Center for Epidemiology, Prevention and Disease Control (CDC Peru) of the Ministry of Health of Peru (Minsa) in coordination with the Pan American Health Organization / World Health Organization (PAHO/WHO), held a virtual session at in order to share information on the epidemiological situation and clinical characterization of Guillain-Barré Syndrome cases in Peru, as well as to share the experience and challenges in responding to this event with other countries in the Americas region.

In this sense, the session was conducted from Washington by officials from the PAHO Health Emergencies department; while the epidemiological presentation was in charge of Dr. César Munayco Escate, general director of the CDC Peru, who during his presentation made a description of the main GBS studies in Peru during the years 2012 - 2017; as well as the analysis and epidemiological characterization of the 2019 outbreak. He also addressed the current situation of GBS in the country, the characteristics of the cases, the advances in investigations; in addition to the public health actions and measures that have been adopted by the Minsa to control the outbreak.

Let us remember that at the national level so far this year, 201 cases of GBS have been reported in 22 regions and 4 deaths (1 Cajamarca, 1 in La Libertad and 2 in Lima). The departments where the highest number of cases are reported are Metropolitan Lima (50), La Libertad (34), Lambayeque (20), Piura (19) and Cajamarca (17). 59.2% of the reported cases correspond to the male sex (119 cases), with adults being the most affected group with 41.8% (84 cases).

Finally, Dr. César Munayco highlighted that the teams from the CDC Peru and the National Epidemiology Network (RENACE) remain attentive to this event and others that could constitute threats to the health of the country's population.

https://www.dge.gob.pe/portalnuevo/informativo/prensa/cdc-peru-y-ops-oms-realizan-sesion-virtual-para-compartir-informacion-sobre-la-situacion-epidemiologica-del-sindrome-de-guillain-barre-en-peru/

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Guillain-Barré Syndrome - Peru

25 July 2023

Situation at a glance

On 26 June 2023, the National Center for Epidemiology, Prevention, and Disease Control (CDC) of Peru issued an epidemiological alert due to an unusual increase in Guillain-Barré Syndrome (GBS) cases in different regions of the country. According to historical data (excluding the 2019 outbreak), the average monthly number of GBS cases registered is less than 20 suspected cases per month nationwide. However, between 10 June – 15 July 2023, 130 suspected cases¹ of GBS have been reported. Out of these cases, 44 have been confirmed. ^2,3 This increase in the number of observed cases is higher than expected.

The Presidency of the Republic of Peru in early July 2023, declared a national health emergency due to the unusual increase and enhanced the implementation of public health responses. To date, the potential cause of the unexpected GBS incidence remains under investigation.

WHO advises Member States to maintain the ongoing monitoring of the incidence and trends of neurological disorders, especially GBS, to identify variations against their expected baseline values and implement protocols for improved patient management. By closely observing and tracking these conditions, countries can effectively respond to any changes and ensure appropriate measures are in place to address potential public health concerns.

Description of the situation

Between epidemiological weeks 1 and 28 (until 15 July 2023), a total of 231 suspected GBS cases were reported in Peru as defined by the National Center for Epidemiology, Prevention, and Disease Control (CDC) Technical Health Standard for Epidemiological Surveillance and Laboratory Diagnosis for GBS¹ in 20 of the country’s 24 departments. Fifty-six percent of the cases (130 cases) were reported between epidemiological weeks 23 (10 June 2023) and 28 (15 July 2023). Since the start of the year, the highest number of GBS cases were recorded in seven of the country’s 24 departments: Lima and Callao (75 cases), La Libertad (39), Piura (21), Lambayeque (20), Cajamarca (17), Junín (12), and Cusco (10). As of 15 July 2023, 100 cases have been confirmed to be compatible with GBS ^2,3, including four deaths (Case Fatality Rate (CFR) 1.7%).

The age group most affected were adults ≥ 30 years (158 cases) while children under 17 years of age accounted for 19% of the cases (44 cases). More than half of the reported cases (133; 57.6%) were males.

The preliminary clinical manifestations of the 130 cases reported between epidemiological weeks 23 (10 July 2023) and 28 (15 July 2023) include gastrointestinal infection, respiratory infection and fever. In addition, 72.3% of these cases (94 cases) presented with upward progression of paralysis as neurological manifestation, with other cases presenting with some type of sequelae.

Samples were collected from the cases according to the technical health standard for epidemiological surveillance and laboratory diagnosis of GBS in Peru. Between epidemiological weeks 23 and 28, 22 samples were collected of which 14 (63%) were positive for Campylobacter jejuni (one of the most common risk factors for GBS) in samples from the departments of La Libertad (5 cases), Lima (4), Piura (3), Cusco (1) and Lambayeque (1), with the sample from Lambayeque further characterised as genotype Campylobacter jejuni sequence type (ST)2993.

Epidemiology of the disease

Guillain-Barré Syndrome (GBS) is a rare neurological disorder of variable clinical severity, including fatal outcomes. It is the most common form of acute flaccid paralysis worldwide and is characterized by motor weakness, areflexia (absence of muscle reflexes), sensory abnormalities, and elevated protein levels in cerebrospinal fluid (cytoalbuminologic dissociation). Most often, an upper respiratory or gastrointestinal illness typically precedes GBS.

There is currently no known cure for GBS. However, people with GBS need supportive treatment, sometimes in intensive care and follow-up. Most treatments available can help manage the symptoms, support the recovery process, and potentially shorten the duration of the illness. Although most cases, even the most serious ones, fully recover, they can produce almost total paralysis. Campylobacter jejuni infection is the most frequently identified precipitant and usually is associated with the acute motor axonal neuropathy form of GBS. While this syndrome is more common in adults and in males, people of all ages can be affected.

In 2019, Peru reported an unprecedented outbreak of GBS that affected several regions of the country, with almost 700 reported cases (incidence: 1.2/100,000 inhabitants). From the clinical-epidemiological characteristics and the study of the identified agents, it was concluded that the outbreak was associated with the presence of the Campylobacter jejuni sequence type (ST) 2993 genotype. In addition, during the year 2020, a total of 448 cases were reported nationally with a weekly average of 11 cases; in 2021, a total of 210 cases were reported with a weekly average of four cases. Similarly, in 2022, there were 225 cases reported with a consistent weekly average of four cases.

Figure 1. Guillain Barré Syndrome case trends in Peru 2021, 2022 and 2023 (Epidemiological week 28)



Source: National Center for Epidemiology, Prevention and Disease Control (CDC) Peru-Peru. The situation of Guillain Barré syndrome -Peru, 2023 (Epidemiological Week 28)

Public health response


The National Center for Epidemiology, Prevention, and Disease Control (CDC) of Peru of the Ministry of Health issued an epidemiological alert on 26 June 2023 and has maintained monitoring of the situation through a GBS Situation Room.

On 8 July 2023, the Presidency of the Republic of Peru declared a national health emergency due to the unusual increase in cases of GBS. The decree provides:

• The implementation of an action plan that includes financing for the provision of strategic resources in health, including the acquisition of 7000 human immunoglobulins as part of the treatment of patients with Guillain Barré syndrome, promoting recovery, and preventing complications associated with the disorder.
• Intensification of surveillance, prevention, and response actions to possible cases.
• Communication of risk to health professionals and issuance of key messages to the population to adopt preventive measures.
• Advice, information, and guidance on Guillain Barré syndrome to health professionals and the general population.

WHO is supporting the health authorities of Peru in the management of this event.

WHO risk assessment


Guillain-Barré syndrome is a rare condition, and while it is more common in adults and males, people of all ages can be affected. The cause of it is not fully understood, but most cases follow an infection with a virus or bacteria. This leads the immune system to attack the body itself. Infection with the bacteria Campylobacter jejuni, which causes gastroenteritis, is one of the most common risk factors for GBS. People can also develop GBS after having the flu or other viral infections, including cytomegalovirus, Epstein-Barr virus, and the Zika virus. In rare instances, vaccinations may increase the risk of people getting GBS, but the likelihood of this occurring is extremely low. Studies show that people are much more likely to get GBS from infections such as the flu than from the vaccine given to prevent the infection, in this case, the flu vaccine. Occasionally, surgery can trigger GBS.

To date, the potential cause of the reported increase in GBS incidence in Peru remains under investigation as Campylobacter jejuni infection was confirmed by the laboratory in 63% of GBS cases from 22 samples tested since epidemiological week 23. In 2019, Peru reported an unprecedented outbreak of Guillain-Barré Syndrome that affected several regions of the country, which was concluded to be associated with the presence of the Campylobacter jejuni ST2993 genotype.

Further investigations are needed to identify the possible causes associated with the increase. So far, no association has been found with the current dengue outbreak, and Zika virus transmission is currently low in the country. Additionally, there have been no reports of a similar surge in cases in other countries of the Americas.

WHO advice


WHO advice to Member States is to continue to monitor the incidence and trends of neurological disorders, especially GBS, to identify variations against their expected baseline values, develop and implement sufficient patient management protocols to manage the additional burden on healthcare facilities generated by a sudden increase in patients with GBS, raise awareness among healthcare workers and establish and/or strengthen links between public health services and clinicians in the public and private sectors.

WHO has not issued any recommendations that would impose travel and/or trade restrictions specifically for Peru in response to this event.

Further information

• National Center for Epidemiology, Prevention and Disease Control (CDC) Peru. CDC Peru issues epidemiological alert due to increase in cases of Guillain Barré Syndrome in some regions of the country. Lima, June 26, 2023. Available from: https://bit.ly/3O6TruV
• Ministry of Health Peru. Minsa issues epidemiological alert for Guillain Barré Syndrome and provides recommendations. 27 June 2023. Available from: https://bit.ly/46Jy4ak
• CDC-Peru. NTS No. 175 - MINSA/2021/CDC Technical Health Standard for Epidemiological Surveillance and Laboratory Diagnosis of Guillain Barré Syndrome in Peru. June 2023. Available from: https://bit.ly/44DlIyE
• CDC-Peru. Situation of Guillain Barré syndrome -Peru, 2023 (Epidemiological Week 27). 10 July 2023. Available from: https://bit.ly/3JS0rJk
• Presidency of the Republic of Peru. Supreme Decree that declares a Health Emergency at the national level due to the unusual increase in cases of Guillain Barré Syndrome. July 8, 2023, Peru. Available from: https://bit.ly/3D4QsfY
• Guillain–Barré syndrome https://www.who.int/news-room/fact-s...C3%A9-syndrome
• Campylobacter https://www.who.int/news-room/fact-s.../campylobacter
• Large Outbreak of Guillain-Barré Syndrome, Peru, 2019 disponible en: https://wwwnc.cdc.gov/eid/article/26/11/20-0127_article
• Munayco, C. V., Gavilan, R. G., Ramirez, G., Loayza, M., Miraval, M. L., Whitehouse, E., Gharpure, R., Soares, J., Soplopuco, H. V., Sejvar, J. (2020). Large Outbreak of Guillain-Barré Syndrome, Peru, 2019. Emerging Infectious Diseases, 26(11), 2778-2780.

1. by the National Center for Epidemiology, Prevention, and Disease Control in the Technical Health Standard for Epidemiological Surveillance and Laboratory Diagnosis for GBS as a person of any age with (i) Bilateral (ascending or descending), symmetrical or relatively symmetrical muscle weakness and (ii) flaccidity and (iii) Diminished or absent deep tendon reflexes in extremities and (iv) with 12 hours to 28 days of evolution from the onset of muscle weakness.
2. A confirmed case of GBS (Level of certainty II) is a suspected case with at least one of the following criteria: (i) Cytological albumin dissociation in cerebrospinal fluid (total leukocyte count < 50 cells/μl and protein elevation > 45 mg/dl). EITHER (i) Electrophysiological study compatible with GBS taken between the second and fourth week of onset of muscle weakness.
3. A confirmed case of GBS (Level of certainty I) is a suspected case with the following two criteria: (i) Cytological albumin dissociation in cerebrospinal fluid (total leukocyte count < 50 cells/μl and protein elevation > 45 mg/dl). AND (i) Electrophysiological study compatible with GBS taken between the second and fourth week of onset of muscle weakness.

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https://www.who.int/emergencies/dise...em/2023-DON477